The Native American Graves Protection and Repatriation Act (NAGPRA), Pub. L. 101-601, 25 U.S.C. 3001 et seq., 104 Stat. 3048, is a United States federal law enacted on November 16, 1990.

The Act includes three major sets of provisions. The "repatriation" provisions of the Act require federal agencies and institutions that receive federal funding to return Native American "cultural items" in their possession or control to lineal descendants and culturally affiliated American Indian tribes, Alaska Native villages, and Native Hawaiian organizations. Cultural items include human remains, funerary objects, sacred objects, and objects of cultural patrimony. A program of federal grants assists in the repatriation process and the Secretary of the Interior may assess civil penalties on museums that fail to comply.

NAGPRA's "disposition" provisions establish procedures for the inadvertent discovery or planned excavation of Native American cultural items on federal or tribal lands, which includes private and state lands within the exterior boundary of an Indian reservation. These provisions do not apply to discoveries or excavations on non-federal or tribal lands, but the repatriation provisions do apply to Native American cultural items if they come under the control of an institution that receives federal funding.

NAGPRA also makes it a criminal offense to traffic in Native American human remains without right of possession or in Native American cultural items obtained in violation of the Act. In the original statute penalties for a first offense could reach 12 months imprisonment and a $100,000 fine. The statute was amended in 2022 to increase the penalty for a first conviction for trafficking Native American human remains from 12 months imprisonment to one year and one day (a felony) and for a subsequent conviction from five years to ten years. An initial conviction for trafficking of Native American cultural items remains a misdemeanor (imprisonment of up to one year), but the penalty for a subsequent conviction was likewise changed from five to ten years.

The Department of the Interior revised the regulations implementing NAGPRA in 2024 to clarify steps for its implementation. The revised regulations, which went into effect on January 12, 2024, state "...museums and Federal agencies must defer to the Native American traditional knowledge of lineal descendants, Indian Tribes, and Native Hawaiian organizations."

The intent of the NAGPRA legislation is to address long-standing claims by federally recognized tribes for the return of human remains and cultural objects unlawfully obtained from pre-contact, post-contact, former, and current Native American homelands. Interpretation of human and Indigenous rights, prehistoric presence, cultural affiliation with antiquities, and the return of remains and objects can be controversial and contested. It includes provisions that delineate the legal processes by which museums and federal agencies are required to return certain Native American cultural items—human remains, gravesite materials, and other objects of cultural patrimony—to proven lineal descendants, culturally-related Native American tribes, and Native Hawaiian groups.

Outcomes of NAGPRA repatriation efforts are slow and cumbersome, leading many tribes to spend considerable effort documenting their requests; collections' holders are obliged to inform and engage with tribes whose materials they may possess. NAGPRA was enacted primarily at the insistence and by the direction of members of Native American nations.

Tribes had many reasons based in law that made legislation concerning tribal grave protection and repatriation necessary.