Jeremy Bentham (; 4 February 1747/8 O.S. [15 February 1748 N.S.] – 6 June 1832) was an English philosopher, jurist, and social reformer regarded as the founder of modern utilitarianism.

Bentham defined as the "fundamental axiom" of his philosophy the principle that "it is the greatest happiness of the greatest number that is the measure of right and wrong." He became a leading theorist in Anglo-American philosophy of law, and a political radical whose ideas influenced the development of welfarism. He advocated individual and economic freedoms, the separation of church and state, freedom of expression, equal rights for women, the right to divorce, and (in an unpublished essay) the decriminalising of homosexual acts. He called for the abolition of slavery, capital punishment and physical punishment, including that of children. He has also become known as an early advocate of animal rights. Though strongly in favour of the extension of individual legal rights, he opposed the idea of natural law and natural rights (both of which are considered "divine" or "God-given" in origin), calling them "nonsense upon stilts". Bentham was also a sharp critic of legal fictions.

Bentham's students included his secretary and collaborator James Mill, the latter's son, John Stuart Mill, the legal philosopher John Austin and American writer and activist John Neal. He "had considerable influence on the reform of prisons, schools, poor laws, law courts, and Parliament itself."

On his death in 1832, Bentham left instructions for his body to be first dissected, and then to be permanently preserved as an "auto-icon" (or self-image), which would be his memorial. This was done, and the auto-icon is now on public display in the entrance of the Student Centre at University College London (UCL). Because of his arguments in favour of the general availability of education, he has been described as the "spiritual founder" of UCL. However, he played only a limited direct part in its foundation.