Siedler is a surname. Notable people with the surname include:
Charles Siedler (1839–1921), German-American politician, 20th Mayor of Jersey City, New Jersey Gerold Siedler (born 1933), German physical oceanographer Norbert Siedler (born 1982), Austrian racing driver Sebastian Siedler (born 1978), former racing cyclist from Germany Wolf Jobst Siedler (1926–2013), German publisher and writer