Cassiem is a South African surname that may refer to:
Aishah Cassiem (born 1992 or 1993), South African politician Dayaan Cassiem (born 1998), South African field hockey player Junaid Cassiem (born 1993), South African former cricketer Mustapha Cassiem (born 2002), South African field hockey player Uzair Cassiem (born 1990), South African rugby union player