Thor

* Abomination - *Enemy*: they clash when both are imprisoned in the world of The Stranger (Thor #178)
* Absorbing Man - *Enemy*: archenemies since Loki created Absorbing Man (Journey into Mystery #114-115). Nickname: "Evil One" (JIM #122)
* Adam Warlock - *Enemy*: they engage in bitter battles when Warlock captures Sif for a mate (Thor #165-166) - *Ally*: both are involved in Infinity War. Nicknames: "Wretched One", "Wretch" and "Villain" (Thor #166)
* Alicia Masters - they meet at the Richards engagement party (Fantastic Four #36) and wedding (An. #3)
* Angel - Thor admires statues of X-Men at the World's Fair (Journey into Mystery #109), their teams have crossed paths several times (since X-Men #9), and Thor saves Angel's life in the Mutant Massacre (Thor #373-374). Nickname: "My Winged Friend" (Thor #374)
* Ant-Man - original Avengers (A #1-16, and from An. #1). Nicknames (Giant-Man): "My Giant Ally" (A #3), "Titanic One" (#12), "Friend Hank" (#69)
* Ares - *Enemy*: they meet when Hercules brings Thor to Olympus (Thor #131), and they battle when Ares goes to war on three worlds (A #98-100) and again at the gates of Hades (Thor #222). Nickname: "Warlord" (A #100)
* Artie Maddicks - Thor saves Artie in the Morlock tunnels (Thor #374)
* Aurora - they take part in the final battle against Beyonder (Secret Wars II.9)
* Avalanche - *Enemy:* the Brotherhood waged war on the Avengers (Annual #10)
* Balder - half-brother and dearest friend. Nicknames: "Brave Balder" (Journey into Mystery #104 - Thor #219), "Loyal Balder" (#104-170), "Loyal One" (Thor #127-176), "Loyal Friend" (#128), "Faithful Friend" (#128, 159), "Valiant Friend" (#129), "Brave One" (#144, 218), "Most Faithful Friend" (#152), "Most Loyal One" (#157), "Most Noble Balder" (#159), "Noble One" and "Gentle Balder" (#162), "Most Noble Friend" (#166)
* Baron Mordo - Doctor Strange tells Thor about Mordo (Journey into Mystery #108)
* Baron Zemo - *Enemy:* major villain for the Avengers (from #6)
* Beast - Thor admires statues of X-Men at the World's Fair (Journey into Mystery #109), their teams have crossed paths several times (since X-Men #9), both members of Avengers
* Beetle - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Beta Ray Bill - they have crossed paths
* Betty Ross - they have crossed paths through Avengers (e.g. #5)
* Bishop - their teams join forces in Onslaught (X-Men #2.55)
* Black Bolt - Thor goes to San Francisco and confronts a Black Bolt impostor (Amazing Adventures #8), and the Inhumans receive help from the Avengers (A #95-96), later Inhumans liberate Avengers and Jarvis from Kang in the 23rd century (MTU #11)
* Black Knight - members of Avengers (from #71)
* Black Panther - Thor observes him from the spaceship of the Collector (Avengers #51), members of the Avengers (on-off from #58). Nickname: "Good T'Challa" (A #84)
* Black Widow - Hawkeye mentions Natasha (Avengers An. #1), later members of Avengers (#111-112)
* Blob - *Enemy:* the Brotherhood waged war on the Avengers (Annual #10)
* Boom-Boom - BB calls the Avengers to warn about The Beyonder (Secret Wars II.5)
* Box - they take part in the final battle against Beyonder (Secret Wars II.9)
* Bulldozer - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Cable - Cable mentions him in his files (X-Force #6)
* Cannonball - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9), but their teams join forces in Onslaught (X-Men #2.55)
* Captain America - core Avengers (A #4-16, and from An. #1). Nickname: "My Valiant Friend" (A #6), "Valiant One" (#10), "Masked One" (An. #2)
* Captain Marvel - they join forces against Skrull impostors in Avengers #92-93
* Carol Danvers - Carol becomes informal member of Avengers (from A #171)
* Charles Xavier - allies many times (since X-Men #9)
* Cloak - they take part in the final battle against Beyonder (Secret Wars II.9), also join forces battling the Jester's Assembly of Evil (C&D #3.9)
* Cobra - *Enemy:* arch enemies since they first battled in India (Journey into Mystery #98)
* Collector - *Enemy:* Thor becomes his unwilling servant (Avengers #51). Nicknames: "Scion of Evil" and "Rash One" (A #51)
* Colossus - they are allies on Beyonder's Battleworld planet (first Secret Wars series) and in the final battle against Beyonder (Secret Wars II.9)
* Count Nefaria - *Enemy:* foes since the battle in Nefaria's American castle (Avengers #13)
* Contessa Valentina - with SHIELD she has on occasion joined forced with the Avengers (e.g. #67)
* Crystal - they talk on video screen from the Refuge (Avengers #110), members of Avengers
* Cyclops - Thor admires statues of X-Men at the World's Fair (Journey into Mystery #109), often allies (since X-Men #9)
* Dagger - they take part in the final battle against Beyonder (Secret Wars II.9), also join forces battling the Jester's Assembly of Evil (C&D #3.9)
* Daredevil - Thor first admires a statue of Daredevil at the World's Fair (Journey into Mystery #109), they meet at the wedding of Reed and Susan Richards (Fantastic Four An. #3), and when DD impersonates Thor (Daredevil #30), later Daredevil frees the Avengers from the villain Aries (Avengers #82), and often alies since then. Nickname: "Masked One" (DD #30)
* Dazzler - X-Men and Avengers go through a series of battles after remnants of Magneto's Asteroid M are found (XM vs A #1-4)
* Doctor Doom - *Enemy*: Doom abducts Thor to Latveria where they do fierce battle (Thor #182-183), later they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Doctor Druid - members of Avengers (from #278)
* Doctor Octopus - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Doctor Strange - Thor saves Strange's life in an operation (Journey into Mystery #108), they meet again at the wedding of Reed and Susan Richards (Fantastic Four An. #3), later join forces against The Beyonder (Secret Wars II.5)
* Doug Ramsey - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* Dragon Man - Goliath talks of Dragon Man being in his suburban house (Avengers #58)
* Drax the Destroyer - both are involved in Infinity War
* Dum Dum Dugan - they meet at the funeral of Captain America (CA #113), and SHIELD has on occasion joined forced with the Avengers (e.g. #67)
* Edwin Jarvis - butler for Avengers (Tales of Suspense #59 - Avengers #16, again from A An. #1)
* Electro - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Enchantress - *Enemy:* eternal archenemy (since before Journey into Mystery #103). Nicknames: "Beautiful One" (JIM #103), "Evil One" (Avengers #84), .................. "Sorceress" (Secret Wars #3), "Fair One" (#4)
* Executioner - *Enemy:* long-time enemies (e.g. Avengers #7)
* Falcon - they team up against a voodoo cult (Avengers #88), and to defend Iron Man against the troops of White Dragon (IM #39)
* Fandral - fellow Asgardians, adventure together (since Journey into Mystery #119). Nicknames: "Dashing One" (Thor #124-195), "Gallant Fandral" (#138), "Dashing Fandral" (#138-162), "Good Friend" (#196), "Brave Fandral" (#213)
* Firelord - they battle but then join forces to defeat and exile Ego (Thor #225-228). Nickname: "Varlet" (Thor #226)
* Firestar - both members of Avengers
* Foggy Nelson - they meet at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Franklin Richards - the superhero teams seek to liberate Franklin in Onslaught
* Gabe Jones - they meet at the funeral of Captain America (CA #113), and SHIELD has on occasion joined forced with the Avengers (e.g. #67)
* Galactus - they clash as Thor interrupts a battle between Galactus and Ego (Thor #161), but Galactus tells Thor his whole life story (#169), they join forces to banish Ego (#226-228), later on opposite sides on Beyonder's Battleworld planet (first Secret Wars series). Nickname: "Space-god" (Thor #228)
* Gambit - their teams join forces in Onslaught (X-Men #2.55)
* Gamora - both are involved in Infinity War
* General Ross - Thor helps the general with tests of missiles (Journey into Mystery #86), they also cross paths through Avengers (A #5) and at the trial of Hulk (Hulk #153)
* Gorgon - Thor reluctantly battles three of the Inhumans in San Francisco (Amazing Adventures #8), later Inhumans liberate Avengers and Jarvis from Kang in the 23rd century (MTU #11)
* Grand Vizier - fellow Asgardians. Nicknames: "Old One" and "Faithful Friend" (Thor #199)
* Green Goblin - Thor hears that Goblin succesfully fought Spider-Man (#18)
* Grey Gargoyle - *Enemy*: they battle repeatedly in Manhattan after Duval first comes to America (Journey into Mystery #107, 113)
* Havok - X-Men and Avengers go through a series of battles after remnants of Magneto's Asteroid M are found (XM vs A #1-4), both are involved in Infinity War, later members of Avengers Unity Squad
* Hawkeye - they briefly meet in Avengers Mansion (Journey into Mystery #120) and also at the wedding of Reed and Susan Richards (Fantastic Four An. #3), members of Avengers together (from A An. #1). Nicknames: "Archer" (A An. #1 - #172), "Valiant One" (A An. #1), "Friend Hawkeye" (#45) ............. Nickname (for Goliath): "Giant" (A #68)
* Heimdall - fellow Asgardian aristocracy. Nickname: "Loyal Heimdall" (Journey into Mystery #110, Thor #200), "Trusty Heimdall" (Thor #159), "Watch-keeper" and "Bold Heimdall" (#193)
* Hela - *Enemy:* primordial opposites (first meeting recounted in Journey into Mystery #102), they then meet at the death of Harokin (Thor #133) and many other confrontations. Nicknames: "Maid of Darkness" (Thor #150), "Most Awesome One" (#154), "Unfeeling One" (#186), "Nightqueen" (#199)
* Henry Gyrich - Gyrich is national security liaison for the Avengers (until #172)
* Hercules - they have a legendary clash in Olympus (Journey into Mystery An. #1), next in Manhattan over the favors of Jane Foster (#125), Hercules lives with the Avengers (from A An. #1 - cA #46), later both members of Avengers. Nicknames: "Insolent One" (JIM An. #1), "Brazen One" (#125), "Rash One" (#126), "Rash Braggart" and "Blustering One" (#128), "Old Friend" and "Bearded One" (Thor #222), "Friend Hercules" (#222-227)
* High Evolutionary - they meet as Thor trespasses High Evolutionary's castle in Wundagore and they battle the Man-Beast (Thor #134-135), and they face the Ani-Mutants together (#475)
* Hildegarde - fellow Asgardians (since Thor #195). Nickname: "Noble Thor" (Thor #213)
* Hogun - fellow Asgardians, adventure together (since Journey into Mystery #119). Nicknames: "My Friend" (Thor #137), "Worthy Hogun" (#139), "Grim One" (#139-198), "Grim Hogun" (#157, 195), "Friend Hogun" (#197, 211), "Bold Hogun" and "Bold Friend" (#202)
* Hulk - original Avengers (A #1-4) and later members again, although they also battle on a Caribbean island because of a dangerous weather machine (Sub-Mariner #35). Nicknames: "Rampaging One", "Violent One" and "Gargantuan One" (Journey into Mystery #112), "Brutish One" (A An. #2), "Monster" and "Man-brute" (Sub-Mariner #35)
* Human Torch - Thor admires statues of Fantastic Four at the World's Fair (Journey into Mystery #109), they meet at the Richards engagement party (Fantastic Four #36) and wedding (An. #3), allies on Beyonder's Battleworld planet (first Secret Wars series) and several times more
* Hydro-Man - *Enemy:* they battle when Hydro-Man is in the Jester's Assembly of Evil (Cloak & Dagger #3.9)
* Iceman - Thor admires statues of X-Men at the World's Fair (Journey into Mystery #109), often allies (since X-Men #9), and Thor saves Iceman from Loki
* Immortus - *Enemy:* arch enemy of Avengers (from #10)
* Iron Fist - they take part in the final battle against Beyonder (Secret Wars II.9)
* Iron-Man - original Avengers (from #1-16, again from An. #1). Nicknames: "Golden One" (A An. #1), "Iron-clad One" (#51)
* J. Jonah Jameson - Hawkeye mentions Jameson and his newspaper (An. Spider-Man #3), Spider-Man namedrops him as well (Avengers #85)
* Jane Foster - his assistant/nurse since before Donald Blake became Thor (Journey into Mystery #84), romantically involved (#97-136). Nicknames as Donald Blake: "Honey" (JM #92, 96, privately), "My Darling" (#97-124), "My Dear" (#99-113), "Jane Dear" (#100, 109), "Jane Darling" (#109), "My Dearest One", "Adored One", "My Most Dearly Beloved" and "Lovely One") (#111, secretly), "My Beloved" (#111-135), "My Dearest" (#113-129), "Button Nose" (#114), "My Loved One" (#115, 129), "Dearest" (#124), "Beloved" and "My Love" (#136)
* Jasper Sitwell - they meet at the funeral of Captain America (CA #113)
* Jean Grey - Thor admires statues of X-Men at the World's Fair (Journey into Mystery #109), often allies (since X-Men #9)
* Juggernaut - they have had battles (mentioned in Thunderstrike #2)
* Julia Carpenter - they are allies on Beyonder's Battleworld planet (first Secret Wars series)
* Kang - *Enemy:* arch enemy of Avengers (from #8). Nicknames: "Villain" and "Braggart" (A #71)
* Karen Page - they meet at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Karma - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* Karnak - Thor reluctantly battles three of the Inhumans in San Francisco (Amazing Adventures #8), later Inhumans liberate Avengers and Jarvis from Kang in the 23rd century (MTU #11)
* Karnilla - classic Asgardian opposites, first directly involved when Thor has lost his powers (Thor #150-152)
* Ka-Zar - Avengers travel to Savage Land and talk of Ka-Zar (A #105)
* Klaw - Black Panther tells Avengers about Klaw (#87), later they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Lady Dorma - they clash on a Caribbean island because of a dangerous weather machine (Sub-Mariner #35)
* Living Laser - *Enemy:* they battle over diamonds in Africa (Avengers An. #1)
* Lizard - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Loki - brother and nemesis. Nicknames: "Evil Brother" (Avengers #1), "Prince of Evil" (Avengers #1, Thor #191), "Evil One" (Journey into Mystery #108 - Thor #200), "Hated One" (JIM #110), "Base Loki" (#126), "Sinister One", "Vile Miscreant, "Most Heinous Betrayer", "Thing of Evil" and "Base-hearted Blackguard" (Thor #153), "Perfidious One" (#155), "Loathsome One" (#157), "Monstrous Villain" (#175), "Conniving One" (#179), "Brother of Evil" (#181), "Vile Villain" (#181), "Base Villain" (#184), "Foul Brother" (#193), "Vile One" (#194), "Monster" (#207)
* Luke Cage - Avengers discuss hypothetically recruiting Cage (Daredevil #99), later they take part in the final battle against Beyonder (Secret Wars II.9)
* Machine Man - in Avengers together(?)(shown in X-51 #2)
* Mad Thinker - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Magik - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* Magma - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* Magneto - *Enemy*: they wage a terrific battle in Magneto's camouflaged submarine (Journey into Mystery #109), also battle in Westchester (Avengers #110-111), and later after remnants of Magneto's Asteroid M are found (XM vs A #1-4) - *Ally*: they are allies on Beyonder's Battleworld planet (first Secret Wars series) and in the final battle against Beyonder (Secret Wars II.9). Nicknames: "Masked One" and "Evil One" (JIM #109), "Jackal" (XM vs A #1)
* Mandarin - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3), and they battle again on his giant space station (Avengers An. #1)
* Mantis - members of Avengers
* Marvel Boy - both members of Avengers
* Maximus - *Enemy:* they battle on Attilan (Avengers #95)
* Medusa - Thor reluctantly battles three of the Inhumans in San Francisco (Amazing Adventures #8)
* Mephisto - *Enemy*: Odin mistakenly sends Thor into the realm of Mephisto, where they battle (Thor #180), later Thor repeats his victory to free his fellow Asgardians (#205). Nicknames: "Monster", "Night-creature", "Black One" and "Villain" (Thor #205)
* Merlyn - Black Knight tells the Avengers about Enchantress and how Merlyn forged the Ebony Blade (A #100)
* Mirage - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9), but later Thor talks to her when he is a frog (NM #38)
* Mister Hyde - *Enemy:* stark enemies ever since Hyde tries to apply to work for Dr. Blake (Journey into Mystery #99). Nicknames: "Evil Braggart" (JIM #106), "Evil One" (#106, 111)
* Mockingbird - a large group of heroes gang up for fights against The Beyonder (Secret Wars II.5, II.9)
* Moira MacTaggert - Moira watches the demise of Avengers as TV-news in Excalibur #102
* Mole Man - *Enemy:* classic villain for the Avengers (since Fantastic Four #31, Avengers #12)
* Monica Rambeau - members of Avengers (from #278)
* Moondragon - both are involved in Infinity War
* Mystique - *Enemy:* the Brotherhood waged war on the Avengers (Annual #10) (Thor later incorrectly talks of Mystique as if she is an unknown entity: All-New X-Men #12)
* Nick Fury - they meet at the wedding of Reed and Susan Richards (Fantastic Four An. #3) and the funeral of Captain America (CA #113), collaborations through Avengers (e.g. A #94)
* Nightcrawler - they are allies on Beyonder's Battleworld planet (first Secret Wars series) and in the final battle against Beyonder (Secret Wars II.9)
* Nighthawk - *Enemy*: four Avengers square off in a game against four from Squadron Sinister (A #70)
* Northstar - they take part in the final battle against Beyonder (Secret Wars II.9)
* Nova - Doctor Doom talks of Galactus being found by Nova (Secret Wars #11)
* Nova (Richard Rider) - both are involved in Infinity War
* Odin - father. Nicknames: "Noblest of Lords" (Journey into Mystery #104), "Noble Lord" (#110), "Noble Father" (#110, 113), "Most Noble Father" (#125), "Most Honored Father" and "Noble Sire" (#128), "Honored Father (#136), "Most Noble Lord" (#140), "Most Noble Monarch" (Thor An. #2), "Most Noble Sire" (#153-184), "Imperial Odin" (#184), "Beloved Liege" (#190), "Noble Odin", "Beloved Father" and "Faithful Liege" (#203)
* Pepper Potts - Avengers gets Pepper on the phone (Tales of Suspense #56)
* Piledriver - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Polaris - both are involved in Infinity War
* Power Man - *Enemy:*as part of Lethal Legion he attacked the Avengers (#79)
* Psylocke - their teams join forces in Onslaught (X-Men #2.55)
* Puck - they take part in the final battle against Beyonder (Secret Wars II.9)
* Pyro - *Enemy:* the Brotherhood waged war on the Avengers (Annual #10)
* Quicksilver - they briefly meet in Avengers Mansion (Journey into Mystery #120) and also at the wedding of Reed and Susan Richards (Fantastic Four An. #3), members of Avengers (from An. #1, and #75-104)
* Rachel Summers - Rachel summons all the heroes to finally end the Beyonder (Secret Wars II.9)
* Radioactive Man - *Enemy:* major enemy (since Journey into Mystery #93)
* Reed Richards - Thor admires statues of Fantastic Four at the World's Fair (Journey into Mystery #109), they meet at the Richards engagement party (Fantastic Four #36) and wedding (An. #3), many team crossovers after that
* Rick Jones - Rick played a major role for the Avengers (from #1)
* Rogue - *Enemy:* Rogue nearly slaughtered all the Avengers (A An. #10), and X-Men and Avengers battle over the remnants of Magneto's Asteroid M (XM vs A #1-4) - *Ally:* on Beyonder's Battleworld planet (first Secret Wars series) and other crossovers, later members of Avengers Unity Squad
* Sabretooth - Wolverine mentions Sabretooth after a battle (All-New X-Men #14)
* Sasquatch - both are involved in Infinity War
* Scarlet Witch - they briefly meet in Avengers Mansion (Journey into Mystery #120), members of Avengers (from An. #1, and from #75)
* Shadowcat - they take part in the final battle against Beyonder (Secret Wars II.9), later the X-Men are confronted by Avengers Unity Squad (All-New X-Men #12-13)
* Shaman - they take part in the final battle against Beyonder (Secret Wars II.9)
* Sharon Carter - they meet at the funeral of Captain America (CA #113) and another funeral (CA #3.46)
* She-Hulk - members of Avengers together
* Sif - fellow gods, they rekindle their romance (since Thor #136), fiancee (from #195). Nicknames: "Lovely Sif" (Thor #136), "Fair One" (#137-204), "Fair Sif" (#137-197), "Lovely One" and "Valiant One" (#139), "Most Lovely Sif" and "Beauteous Sif" (#155), "Most Fair Sif" (#157), "Beloved" (163-189), "My Love" (#165, 216), "Beloved Sif" (#166), "My Lady/Milady Sif" (#166, 202), "Most Truly Beloved" (#167), "Beauteous One" (Avengers #105), "Fair Lady" (Thor #206) .......... "Radiant Goddess" (Thor #329). Nickname (as Blake): "Young Lady" (Thor #154)
* Silver Surfer - they clash because Loki tries to get the Surfer to assassinate Thor (SS #4), and on a Caribbean island because of a dangerous weather machine (Sub-Mariner #35), but become allies when Surfer saves Thor from Durok (Thor #193) and later on. Nickname: "Rider of the Silver Spaceboard" (SS #4)
* Snowbird - they take part in the final battle against Beyonder (Secret Wars II.9)
* Speed Demon - *Enemy*: four Avengers square off in a game against four from Squadron Sinister (A #70)
* Spider-Man - Thor first hears of Spider-Man (Avengers #3 and Journey into Mystery #109), Spidey saves the Avengers from Kang's Spider-Man robot (Avengers #11), many collaborations after that
* Spider-Woman (JD) - members of Avengers
* Starfox - both are members of Avengers
* Storm - they are allies on Beyonder's Battleworld planet (first Secret Wars series), but X-Men and Avengers go through a series of battles after remnants of Magneto's Asteroid M are found (XM vs A #1-4), later meet at the X-Mansion (All-New X-men #8)
* Strong Guy - both are involved in Infinity War
* Sub-Mariner *- Enemy:* Namor battles the Avengers (A #3-4) and also on a Caribbean island because of a dangerous weather machine (Sub-Mariner #35) - *Ally*: in the final battle against Beyonder (Secret Wars II.9). Nickname: "Sea Prince" (A #4)
* Super-Skrull - *Enemy*: they battle when Loki sends the Super-Skrull to Earth to vanquish Thor (Thor #142)
* Supreme Intelligence - they meet on Hala after the Intelligence has allied with Rick Jones (Avengers #97)
* Super-Skrull - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3), have had other battles (mentioned in Captain Marvel #2)
* Susan Richards - Thor admires statues of Fantastic Four at the World's Fair (Journey into Mystery #109), they meet at the Richards engagement party (Fantastic Four #36) amd wedding (An. #3), allies against The Beyonder (Secret Wars II.5, II.9) and later
* Swordsman - *Enemy:*as part of Lethal Legion he attacked the Avengers (#79) - *Ally*: they join forces against Ares and his war on three worlds (A #100), members of Avengers
* Talisman - they take part in the final battle against Beyonder (Secret Wars II.9)
* The Thing - Thor admires statues of Fantastic Four at the World's Fair (Journey into Mystery #109), they meet at the Richards engagement party (Fantastic Four #36) and wedding (An. #3), allies on Beyonder's Battleworld planet (first Secret Wars series) and later
* The Watcher - Galactus tells Thor a story of one of Watcher's travels (Thor #168-169), later Watcher confides with Avengers after their battles with Leonard Tippit (#101), and they meet again after Kryllk has stolen The Watcher's Dark Crystal (MTU #7)
* Thunderball - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Thunderstrike - they are associates and at one point merge
* Tigra - a large group of heroes gang up for fights against The Beyonder (Secret Wars II.5, II.9)
* Titania - they are on opposite sides on Beyonder's Battleworld planet (first Secret Wars series)
* Trapster - Avengers contact Paste-Pot Pete while he is in prison (Avengers #6)
* Triathlon - members of Avengers
* Triton - Triton and the Inhumans get help from the Avengers (#95-96), later Inhumans liberate Avengers and Jarvis from Kang in the 23rd century (MTU #11)
* Two-Gun Kid - the Avengers discuss Two-Gun Kid (A #172)
* Ulik - *Enemy*: archenemy (since Thor #137). Nicknames: "Savage One", "Base Troll" and "Bestial One" (Thor #152), "Thing of Evil" and "Merciless One" (#173), "Monster" (#210)
* Viper - *Enemy*: Madame Hydra attacks and gasses the entire funeral party for Captain America (CA #113), later Avengers battle Madame Hydra at Avengers Tower in All-New X-Men #8
* Vision - members of Avengers (on-off from A #58). Nicknames: "Insolent One" and "Tormented One" (A #58), "Android" (#98)
* Volstagg - fellow Asgardians, adventure together (since Journey into Mystery #119). Nicknames: "Enormous One" (JIM #122), "Valiant Volstagg" (Thor #128), "Most Voluble One" and "Mountainous Friend" (#136), "Voluminous One" (#140, 212), "Valorous Volstagg" (#145), "Old Friend" (#189), "Red-beard" and "Fat One" (#198), "Loud Volstagg" (#204)
* Warlock - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* War Machine - members of Avengers
* Wasp - original Avengers (#1-16 and from An. #1)
* Whirlwind - *Enemy*: they take part in the big battle at the wedding of Reed and Susan Richards (Fantastic Four An. #3)
* Winter Soldier - Thor hears about Bucky from Cap (Avengers #4),
* Wolfsbane - New Mutants attack all assembled heroes after becoming Beyonder's slaves (Secret Wars II.9)
* Wolverine - they are allies on Beyonder's Battleworld planet (first Secret Wars series) and in the final battle against Beyonder (SW II.9), but X-Men and Avengers battle after remnants of Magneto's Asteroid M are found (XM vs A #1-4), plus more crossovers
* Wonder Man - WM associated himself with the early Avengers (from #9), later both fight against The Beyonder (Secret Wars II.5, II.9)
* Wrecker - *Enemy*: archenemy since Wrecker gained the power of Loki (Thor #148). Nicknames: "Villain" and "Evil One" (Thor #171)
* X-Man - X-Man meets with the Avengers to warn them about Onslaught (Onslaught: X-Men)
* Zeus - they meet in Olympus as Zeus ends the battle with Hercules (Journey into Mystery An. #1), Thor is witness as Zeus sends Pluto back to the underworld (Thor #164), and later he stays a while as guest at Zeus' court (#222)