Oosthuizen is a South African surname, especially common among Afrikaners. Notable people with the name include:
Caylib Oosthuizen (born 1989), South African rugby union player
Coenie Oosthuizen (born 1989), South African rugby union player
D. C. S. Oosthuizen (born 1926; also known as Daantjie Oosthuizen), South African philosopher
Devin Oosthuizen (born 1988), South African rugby union player
Etienne Oosthuizen (born 1992), South African rugby union player
Etienne Oosthuizen (born 1994), South African rugby union player
John Robert Oosthuizen (born 1987), South African javelin thrower
Louis Oosthuizen (born 1982), South African professional golfer
Nicolaas Oosthuizen (born 1996), South African rugby union player
Ockie Oosthuizen (born 1955), South African rugby union player
Theo Oosthuizen (born 1964), South African rugby union player and coach
Thomas Oosthuizen (born 1989), South African professional boxer
Also:
Deon Oosthuysen (born 1963), South African rugby union player and coach
