Niemann is a Low German surname. Notable people with the surname include:
Albert Niemann (chemist) (1834–1861), German chemist
Albert Niemann (paediatrician) (1880–1921), German physician
Albert Niemann (tenor) (1831–1917), German opera singer
Brausch Niemann (born 1939), South African racing driver
Carl Niemann (1908–1964), American biochemist
Edmund John Niemann (1813–1876), British artist
Gunda Niemann-Stirnemann (born 1966), German speed skater
Jeff Niemann (born 1983), American baseball player
Jerrod Niemann (born 1979), American country music singer
Johan Niemann (born 1977), Swedish bassist
Johann Niemann (1913–1943), Nazi SS officer
Kristian Niemann (born 1971), Swedish guitarist
Randy Niemann (born 1955), American baseball coach and player
