Trinity College is a constituent college of the University of Cambridge in England. With around 700 undergraduates, 430 graduates, and 170 fellows, it is the largest college in either Oxford or Cambridge. In terms of student numbers, it is second to Homerton College, Cambridge.

In the 20th century, members of Trinity won 31 Nobel Prizes (of the 75 won by members of Cambridge University), and five Fields Medals in Mathematics (of the six awarded to members of British universities).

Since 2000 the college has always come at least eighth in the Tompkins Table, which ranks the 29 Cambridge colleges according to the academic performance of their undergraduates, and on two occasions it has been in first place. Its average position has been fourth. On this benchmark, it has been behind Emmanuel (average second place) and above Christ's (average fifth place). In 2011, 37% of Trinity undergraduates achieved Firsts - a recent record among Cambridge colleges.

Trinity is one of Cambridge University's three royal colleges, along with King's and St John's.

Two members of the British Royal Family have studied at Trinity and been awarded degrees as a result: Prince William of Gloucester and Edinburgh, who gained an MA in 1790, and Prince Charles, who was awarded a lower second class BA in 1970. Other British Royal family members have studied there without obtaining degrees, including King Edward VII, King George VI, and Prince Henry of Gloucester.

Currently about 60% of Trinity's undergraduates went to private schools. In 2006 it accepted a smaller proportion of students from state schools (39%) than any other Cambridge college, and on a rolling three-year average it has admitted a smaller proportion of state school pupils (42%) than any other college at either Cambridge or Oxford. According to the Good Schools Guide, about 7% of British school-age students attend private schools. Trinity states that it disregards what type of school its applicants attend, and accepts students solely on the basis of their academic prospects.

Trinity admitted its first woman graduate student in 1976 and its first woman undergraduate in 1978, and appointed its first female fellow in 1977.

In 2011, the John Templeton Foundation awarded Trinity College's Master, Baron Rees of Ludlow, its controversial million-pound Templeton Prize.

Trinity alumni include six British prime ministers (all Tory or Whig/Liberal), British King George VI, several heads of other nations, physicists Isaac Newton and Niels Bohr, philosophers Ludwig Wittgenstein and Bertrand Russell (whom it expelled before reaccepting), and Soviet spies Kim Philby, Guy Burgess, and Anthony Blunt.

Trinity has many college societies, including the Trinity Mathematical Society, which is the oldest mathematical university society in the United Kingdom, and the First and Third Trinity Boat Club, its rowing club, which gives its name to the college's May Ball. Along with King's and St John's colleges, it has also had several members who have belonged to the Apostles, an intellectual secret society.

In 1848, Trinity hosted the meeting at which Cambridge undergraduates representing private schools such as Westminster drew up the first formal rules of football, known as the Cambridge Rules.

Trinity's sister college in Oxford is Christ Church. Like that college, Trinity has been linked with Westminster School since the school's refoundation in 1560, and its Master is an ex officio governor of the school.