Joslin is a surname. Notable people with the surname include:
Alfred H. Joslin (c. 1914–1991), American judge
David B. Joslin (born 1936), American bishop
Derek Joslin (born 1987), Canadian professional ice hockey defenceman
Elliott P. Joslin (1869–1962), first doctor in the United States to specialize in the treatment of diabetes Les Joslin (born 1947), Australian cricketer Margaret Joslin (1983–1956), American film actress Murray Joslin (1901–1981), American electrical engineer who made major contributions to nuclear power Peter Joslin (born 1933), British police officer, Chief Constable of Warwickshire Police and Deputy Lieutenant of Warwickshire Phil Joslin (footballer) (1916–1980), English professional footballer Phil Joslin (referee) (born 1959), English association football referee Raymond E. Joslin (1936–2013), American businessman and cable executive Rebecca Richardson Joslin (1846–1934), American author, lecturer, benefactor, clubwoman Sesyle Joslin (born 1929), American children's author Theodore Goldsmith Joslin (1890–1944), press secretary to President Herbert Hoover from 1931 to 1933 Isaac Joslin Cox (1873–1956), American professor of history