Sillett is a surname. Notable people with the surname include:
Charlie Sillett (1906–1945), English professional footballer Emma Sillett (1802–1880), English painter James Sillett (1764–1840), English painter John Sillett (1936–2021), English football player and manager Keith Sillett (born 1929), Australian cricket player Pauline Sillett (born 1949), British swimmer Peter Sillett (1933–1998), English football player Stephen C. Sillett (born 1968), American botanist