The Patriot League is a collegiate athletic conference comprising primarily leading private institutions of higher education and two United States service academies based in the Northeastern United States. Except for the Ivy League, it is the most selective group of higher education institutions in the National Collegiate Athletic Association (NCAA) Division I and has a very high student-athlete graduation rate for both the NCAA graduation success rate and the federal graduation rate.

The Patriot League has 10 core members: American University, the United States Military Academy (Army), Boston University, Bucknell University, Colgate University, College of the Holy Cross, Lafayette College, Lehigh University, Loyola University Maryland, and the United States Naval Academy (Navy). All 10 core members participate in the NCAA Division I for all Patriot League sports that they offer. Since not all schools sponsor every available NCAA sport, most schools are affiliated with other collegiate conferences for sports such as ice hockey and wrestling.

Only half of the conference's core members compete in the Patriot League for football, as part of the NCAA Division I Football Championship Subdivision (FCS): Bucknell, Colgate, Holy Cross, Lafayette, and Lehigh. Of the five other conference members, American, Boston University, and Loyola Maryland do not sponsor football, while Army and Navy play in the NCAA Division I Football Bowl Subdivision as football-only members of the American Athletic Conference (The American).

Five other institutions are Patriot League members only for specific sports, and are referred to as associate members. Fordham University, Georgetown University, and the University of Richmond are associate members in football, while Georgetown and the Massachusetts Institute of Technology (MIT) are associate members in women's rowing. Two more schools will join as associate members for football in 2026—Villanova University and the College of William & Mary.

Patriot League members are schools with very strong academic reputations that adhere strongly to the ideal of the "scholar-athlete", with the emphasis on "scholar". An academic index ensures that athletes are truly representative of and integrated with the rest of the student body. Out-of-league play for Patriot League schools is often with members of the Ivy League, which follow similar philosophies regarding academics and athletics.

Patriot League members have some of the oldest collegiate athletic programs in the country. In particular, "The Rivalry" between Lehigh University and Lafayette College is both the nation's most-played and longest-uninterrupted college football series.

The winner of the Patriot League basketball tournament receives an automatic invitation to the NCAA Division I basketball tournament every March. In recent years, Bucknell (twice) and Lehigh have both won NCAA tournament games. The Patriot League champions in a number of other sports also receive an automatic invitation to their respective NCAA tournaments.

The origins of the Patriot League began after the eight Ivy League schools expanded their football schedules to ten games starting in 1980. Needing opponents with a similar competitive level on a regular basis for each team's three nonconference games, the league contacted two university presidents, the Reverend John E. Brooks, S.J., of Holy Cross, and Peter Likins of Lehigh, about forming a new conference that also prohibited athletic scholarships. The result was the Colonial League, a football-only circuit that began competition in 1986. Its six charter members were Holy Cross, Lehigh, Bucknell, Colgate, Lafayette, and Davidson. Davidson dropped out after the 1988 season for reasons related to geography, lack of competitiveness, and a reluctance to relinquish its basketball scholarships in case the conference expanded into other sports.