Justice Brennan may refer to:
William J. Brennan Jr. (1906–1997), former Justice of the Supreme Court of the United States Gerard Brennan (1928-2022), former Chief Justice of Australia and former judge of the Hong Kong Court of Final Appeal Thomas E. Brennan (1929–2018), former Chief Justice of the Michigan Supreme Court and founder of the Thomas M. Cooley Law School
See also Judge Brennan (disambiguation)