Joslin is a surname. Notable people with the surname include:
Alfred H. Joslin (1914–1991), American judge Andrew Joslin (born 1989), English cricketer 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 Graeme Joslin (born 1950), Australian rules footballer Jervis Joslin (1835–1899), American politician Joan Joslin (1923–2020), English codebreaker at Bletchley Park Les Joslin (born 1947), Australian cricketer Les Joslin (author) (born 1943), American retired naval officer, natural resource manager, educator, and author Margaret Joslin (1883–1956), 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 Samuel Joslin (born 2002), British film and television actor Sesyle Joslin (born 1929), American children's author Theodore Joslin (1890–1944), press secretary to President Herbert Hoover from 1931 to 1933 William H. Joslin (1829–1926), American politician