A heterogeneous material joint structure comprising: a resin panel (18, 20) that is configured by a fiber reinforced plastic and that is formed with a plurality of first holes (34, 54) in a row along a vehicle front-rear direction at either vehicle width direction side portion of the resin panel (18, 20); a metal panel (14, 16) that is configured by a metal and that includes a left and right pair of first reinforcements that extend along the vehicle front-rear direction and are formed with a plurality of second holes (36, 56) at locations facing the first holes, and a second reinforcement that extends along the vehicle width direction between the first reinforcements and has both vehicle width direction end portions joined to the first reinforcements; and rivets that are inserted into the first holes (34, 54) and into the second holes (36,56), that join the resin panel (18, 20) and the metal panel (14, 16) together in a state in which a head portion configuring one end portion of each of the rivets is disposed at the resin panel side and a flange portion configuring another end portion of each of the rivets is disposed at the metal panel side, a diameter dimension of the head portion being set larger than a diameter dimension of the flange portion, wherein: recessed portions (30, 50) that project out from a general portion of the resin panel toward the metal panel side and abut the metal panel are formed in the resin panel; the first holes (34, 54) are formed in the respective recessed portions; and the head portion of each of the rivets is closer to the metal panel than a respective surface of the general portion (18A, 20A) of the resin panel (18, 20) that is further away from the metal panel. a resin panel (18, 20) that is configured by a fiber reinforced plastic and that is formed with a plurality of first holes (34, 54) in a row along a vehicle front-rear direction at either vehicle width direction side portion of the resin panel (18, 20); a metal panel (14, 16) that is configured by a metal and that includes a left and right pair of first reinforcements that extend along the vehicle front-rear direction and are formed with a plurality of second holes (36, 56) at locations facing the first holes, and a second reinforcement that extends along the vehicle width direction between the first reinforcements and has both vehicle width direction end portions joined to the first reinforcements; and rivets that are inserted into the first holes (34, 54) and into the second holes (36,56), that join the resin panel (18, 20) and the metal panel (14, 16) together in a state in which a head portion configuring one end portion of each of the rivets is disposed at the resin panel side and a flange portion configuring another end portion of each of the rivets is disposed at the metal panel side, a diameter dimension of the head portion being set larger than a diameter dimension of the flange portion, wherein: recessed portions (30, 50) that project out from a general portion of the resin panel toward the metal panel side and abut the metal panel are formed in the resin panel; the first holes (34, 54) are formed in the respective recessed portions; and the head portion of each of the rivets is closer to the metal panel than a respective surface of the general portion (18A, 20A) of the resin panel (18, 20) that is further away from the metal panel. recessed portions (30, 50) that project out from a general portion of the resin panel toward the metal panel side and abut the metal panel are formed in the resin panel; the first holes (34, 54) are formed in the respective recessed portions; and the head portion of each of the rivets is closer to the metal panel than a respective surface of the general portion (18A, 20A) of the resin panel (18, 20) that is further away from the metal panel.