Westerman is a surname. Notable people with the surname include:
Alan Westerman (1913–2001), senior Australian public servantAlex Westerman (born 1969), American Creative DirectorChantal Westerman American actress and television correspondentFloyd "Red Crow" Westerman (1936–2007), Lakota musician, songwriter, and actorGwen Westerman, a Dakota educator, writer and artistJohn F. C. Westerman (1901-1991), English children's books authorHarold Westerman (1917-2011), American college football and basketball coachHelen Westerman (1926-2006), All American Girls Professional Baseball League playerPercy F. Westerman (1876–1959), English children's books author