Tau ngam hat nhan (tieng Anh: Nuclear submarine) la mot loai tau ngam van hanh nho nang luong sinh ra tu phan ung hat nhan ben trong Lo phan ung hat nhan cua tau. Loai tau ngam nay co rat nhieu nhung loi the ve hieu nang hoat đong so voi loai tau ngam diesel - đien truoc đo. Nho co suc đay hat nhan ma loai tau nay khong con phu thuoc vao khong khi, do đo tau ngam khong nhat thiet phai noi len mat nuoc thuong xuyen. Mat khac, voi nguon nang luong khong lo tu hat nhan, tau ngam hat nhan co the van hanh toc đo cao trong mot thoi gian dai, va thoi gian tieu thu nhien lieu cung đuoc mo rong, chi tru truong hop phai tiep te đo an. Voi the he tau ngam hat nhan hien tai thi no co the van hanh trong 25 nam lien tuc ma khong phai nap nhien lieu.
Mat khac, tau ngam hat nhan cung co điem yeu so voi tau ngam chay bang dau diesel, đo la phai lien tuc lam mat lo phan ung hat nhan ke ca khi tau khong di chuyen; khoang toi 70% luong nhiet tu lo thoat ra va truyen vao nuoc bien. Đieu nay se tao nen "vung day song nhiet", mot luong nuoc am co mat đo thap noi len tren be mat bien. Do đo se tao nen "vet nhiet" ma đoi phuong co the quan sat đuoc nho he thong do anh nhiet, vi du FLIR. Mot van đe khac đo la lo phan ung chay lien tuc chu khong the ngat đi nhu đong co dau, do đo tao nen tieng hoi nuoc va rat de bi phat hien boi sonar, va may bom lam mat lo phan ung cung phai chay lien tuc (dung cho chu trinh tai nhiet, neu khong thi lo phan ung se qua nong va phat no) cung se tao ra tieng đong, trai nguoc voi tau ngam diesel-đien co the di chuyen hoac an nap mot cach tinh lang voi đong co đien. Ngoai ra, van đe moi truong cung la mot quan ngai lon, vi neu tau ngam hat nhan gap tai nan hoac bi đanh trung thi se gay ra nguy co o nhiem hat nhan cho ca mot vung bien lon.
Hien nay, chi co luc luong hai quan cua 5 quoc gia thanh vien Hoi đong Bao an Lien Hop Quoc la: Hoa Ky, Lien Xo (sau khi Lien Xo sup đo la Nga), Anh, Phap va Trung Quoc la co ham đoi tau ngam hat nhan, trong đo, Hai quan My co 100% ham đoi tau ngam đeu la tau ngam hat nhan. An Đo la quoc gia duy nhat khong thuoc Hoi đong Bao an Lien Hop Quoc co trang bi tau ngam hat nhan, đo la chiec INS Charka, mot chiec tau ngam hat nhan lop Shchuka-B ma nuoc nay thue lai trong 10 nam tu Nga. Truoc đo, Hai quan An Đo cung co thue chiec tau ngam K-43, mot chiec tau ngam hat nhan lop Charlie cua Lien Xo tu nam 1987 đen nam 1991. Hien nay, An Đo đang tu phat trien tau ngam hat nhan lop Arihant cho rieng minh.


Lich su Y tuong che tao mot loai tau ngam chay bang hat nhan đuoc khoi xuong boi Phong thi nghiem Nghien cuu Hai quan (Naval Research Laboratory) tu nam 1939. Nha vat ly nguoi My Ross Gunn (1897-1966) đuoc to New York Times khen ngoi la: "Mot trong nhung cha đe cua chuong trinh tau ngam hat nhan".
Nam 1954, My đa cho ha thuy chiec tau ngam hat nhan đau tien tren the gioi, chiec USS Nautilus, mang ma hieu SSN-571. No đa pha vo nhieu ki luc ve toc đo, thoi gian va kha nang chiu đung ap luc khi lan cua cac tau ngam diesel-đien Klasse XXI truoc đo cua Đuc Quoc Xa. 
Phong thi nghiem Nang luong Nguyen tu Bettis (thuoc tap đoan Westinghouse) đam nhan viec che tao lo phan ung hat nhan, trong khi cong ty Electric Boat, mot cong ty con cua tap đoan General Dynamics, đam nhan viec che tao con tau. Sau khi hoan thanh, Đe Nhat Phu nhan Hoa Ky Mamie Eisenhower, vo cua tong thong Dwight D. Eisenhower, đa an mung bang mot chai champagne tren mui con tau. Vao ngay 17/1/1955, con tau đuoc ha thuy đe chay thu sau khi roi cang Gorton, Connecicut. Tau Nautilus co chieu dai 320 feet (98 m), chi phi cho viec che tao la 55 trieu USD (Đola My thoi gia 1954).
Trong thap nien 50, Hai quan Lien Xo cung bat đau viec che tao tau ngam hat nhan đe tao the can bang voi Hai quan My trong Chien tranh Lanh. Hai quan Lien Xo bat đau hang loat cac thu nghiem phan ung hat nhan tai Vien Vat ly va Ky thuat Đien o Obninsk. Đen nam 1956, lo phan ung hat nhan đuoc phat trien boi đoi ngu cac nha vat ly gioi nhat cua Lien Xo duoi su lanh đao cua Anatoly Petrovich Aleksandrov (1903-1994) đa san sang đi vao hoat đong, trong khi đo, mot nhom cac ky su cua Sevmash (duoi su lanh đao cua Vladimir N. Peregudov) đa thiet ke phan than cua con tau. Vuot qua moi chuong ngai, bao gom van đe ve may phat hoi nuoc, ro ri phong xa, va nhung kho khan khac, tau ngam hat nhan mang ten K-3 "Leninskiy Komsomol" cua du an 627 "Kit" (Project 627 Kit, tieng Nga: Кит), con goi la lop November (November-class) cua NATO đa đuoc đua vao hoat đong vao Hai quan Lien Xo trong nam 1958.
Voi nang luong hat nhan, viec che tao bo phan đay cho ten lua đan đao tau ngam chien luoc tro nen ly tuong, nho đo tang kha nang giu duoi nuoc va khong bi phat hien. tau ngam hat nhan voi ten lua đan đao chien luoc đau tien co ten la USS George Washington (SSBN-598) voi 16 qua ten lua Polaris A-1. Lien Xo cung đa co mot vai tau ngam hat nhan trong du an 629 (lop Golf), va chi sau 1 nam, tau ngam K-19 cua du an 658 (lop Hotel) đa đuoc hoat đong lan đau vao thang 11-1960.


Cong nghe cua tau ngam hat nhan Điem khac biet chinh giua tau ngam hat nhan loai thuong va loai hat nhan la o he thong phat nang luong. Tau ngam hat nhan su dung lo phan ung hat nhan cho viec phat nang luong. Cac lo phan ung con co the cung cap đien cho motor đien noi voi chan vit hoac su dung phan ung toa nhiet đe san xuat hoi nuoc, phuc vu cho viec quay turbine hoi nuoc. Cac lo phan ung su dung nhien lieu đa đuoc lam giau uranium 235 (thuong hon 20%), nho đo ma se san sinh ra mot luong cong suat khong lo, giup cho tau ngam hat nhan co the van hanh trong thoi gian dai - đieu ma kho co the thuc hien do vi tri cua lo phan ung co the nguy hiem vi ap suat lon cua than tau.
Lo phan ung hat nhan cung co the cung cap nguon cho cac he thong ngam khac, nhu la can bang duong khi, san xuat nuoc uong bang viec bo muoi tu nuoc bien, đieu chinh ap suat va van van. Tat ca cac lo cua hai quan hien tai đeu van hanh voi may phat diesel va he thong khoi phuc nguon. Nhung đong co nay co kha nang cung cap nguon đien khan cap phong khi lo qua tai nhiet, cung nhu la đu đien cung cap cho bo phan đay bang co hoc. tau ngam hat nhan co the van hanh toi 30 nam khi mang nhien lieu hat nhan. Tro ngai duy nhat lam gioi han thoi gian o duoi nuoc cua tau ngam hat nhan la su cung cap thuc an va bao tri than tau.


Danh sach cac tau ngam hat nhan = My =


 Ngung hoat đong  SCB-64: USS Nautilus (SSN-571)
SCB-64A: USS Seawolf (SSN-575)
SCB-121: Skate class attack submarines
SCB-132: USS Triton (SSRN-586)
SCB-137A: USS Halibut (SSGN-587)
SCB-154: Skipjack class attack submarines
SCB-178: USS Tullibee (SSN-597)
SCB-180A: George Washington class ballistic missile submarines
SCB-180: Ethan Allen class ballistic missile submarines
SCB-188: Permit class attack submarines
SCB-188A: Sturgeon class attack submarines
SCB-216: Lafayette class ballistic missile submarines
SCB-216: James Madison class ballistic missile submarines
SCB-216: Benjamin Franklin class ballistic missile submarines
NR-1
SCB-245: USS Narwhal (SSN-671)
SCB-302: USS Glenard P. Lipscomb (SSN-685)


 Đang hoat đong  SCB-303: Lop Los Angeles
SCB-304: Lop Ohio
Lop Seawolf
Lop Virginia


 Đang phat trien  Ohio replacement SSBN(X) (In development)


= Lien Xo/Nga =


 Ngung hoat đong  Project 627 (November) attack submarines
Project 645 test attack submarine K-27
Project 658 (Hotel) ballistic missile submarines
Project 659/675 (Echo) cruise missile submarines
Project 661 (Papa) attack submarines
Project 667 (Yankee) ballistic missile submarines
Project 667B, Murena (Delta I) ballistic missile submarines
Project 667BD, Murena-M (Delta II) ballistic missile submarines
Project 670 (Charlie) cruise missile submarines
Project 671 (Victor) attack submarines
Project 678 (X-Ray) research submersible
Project 685 (Mike) attack submarine K-278 Komsomolets
Project 705 (Alfa) attack submarines


 Đang van hanh  Project 941 (Typhoon) ballistic missile submarines
Project 945 (Sierra) attack submarines
Project 949 (Oscar) cruise missile submarines
Project 667BDR, Kalmar (Delta III) ballistic missile submarines
Project 667BDRM, Delfin (Delta IV) ballistic missile submarines
Project 1910 Kashalot-class (Uniform) special purpose submarines
Project 1851.1 (Paltus) special purpose submarines
AS-12 (Losharik) special purpose submarine
Project 971 (Akula) attack submarines
Project 671RTM Shchuka (Victor III) attack submarines
Project 935 (Borei) ballistic missile submarines(Russian submarine Yury Dolgorukiy).(2 sea trials)


 Đang phat trien  Project 885 (Graney) attack submarines (Sea trials)


= Vuong Quoc Anh =


 Ngung hoat đong  HMS Dreadnought (S101)
Valiant class attack submarines
Resolution class ballistic missile submarines
Churchill class attack submarines
Swiftsure class attack submarines


 Đang van hanh  Trafalgar class attack submarines
Vanguard class ballistic missile submarines
Astute class attack submarines


 Đang phat trien  Vanguard replacement SSBN (In development)


= Phap =


 Ngung hoat đong  Redoutable class ballistic missile submarines


 Đang van hanh  Rubis class attack submarines
Triomphant class ballistic missile submarines


 Đang phat trien  Barracuda class attack submarines (In development)


= Trung Quoc =


 Đang van hanh  Type 091 (Han) attack submarines
Type 092 (Xia) ballistic missile submarines
Type 093 (Shang) attack submarines
Type 094 (Jin) ballistic missile submarines


 Đang phat trien  Type 095 attack submarines (In development)
Type 096 (Tang) ballistic missile submarines (In development)


= An Đo =


 Ngung hoat đong  INS Chakra: thue lai chiec K-43 (lop Charlie) tu Lien Xo trong giai đoan 1987-1991


 Đang van hanh  INS Chakra: thue lai chiec Nerpa K-152 (lop Akula) tu Nga vao nam 2011 (đam phan tu 2008)
Arihant class submarine - INS Arihant (đang thu nghiem o)


 Đang phat trien  Arihant class submarine -  1 in sea trial as INS Arihant, 1 or 2 under construction next one is named INS Aridhaman)
Indian Navy SSN programme - 6 submarines to be built.


= Brazil =


 Đang phat trien  SNB Alvaro Alberto - SN10 attack submarines


Tham khao Lien ket ngoai Nuclear submarine tai Encyclopædia Britannica (tieng Anh)
Nuclear Propulsion – Federation of American Scientists 29/2/2000
V.M. Bukhalov – Atomic-powered submarine design
Fast Attacks and Boomers: Submarines in the Cold War An online exhibition from the National Museum of American History, Smithsonian Institution
On Eternal Patrol, website listing all US submarines and submariners lost on duty
The Russian Northern Fleet Nuclear-powered vessels Thomas Nilsen, Igor Kudrik and Alexandr Nikitin 28/9/1997
The Russian Northern Fleet Nuclear submarine accidents Luu tru ngay 29 thang 12 nam 2014 tai Wayback Machine Thomas Nilsen, Igor Kudrik and Alexandr Nikitin 5/10/1997
The Russian Northern Fleet Appendix Thomas Nilsen, Igor Kudrik and Alexandr Nikitin 28/9/1997