Neidhardt is a surname of German origin. Notable people with the surname include:
Elke Neidhardt (1941–2013), German-Australian actress Franjo Neidhardt (1907–1984), Croatian architect Frederick C. Neidhardt (1931–2016), American microbiologist Juraj Neidhardt (1901–1979), Yugoslav architect Velimir Neidhardt (born 1943), Croatian architect John G. Neihardt (1881-1973), American poet, author, and ethnographer