A fluid pump, in particular a water pump, has a pump housing (11) that surrounds a pump wheel and a motor housing, connected to the pump housing, in which an electric motor (21) driving the pump wheel is received along with a stator (22) and rotor. For the sake of sealing off the pump from the escape of fluid and sealing off the motor housing from the penetration of fluid, with only one seal, and with assembly of the fluid pump without additional connecting elements, the pump housing (11) has a lower housing part (12) with an annular rib (14) protruding radially outward, and an upper housing part (13) slipped onto the lower housing part (12). Between the free annular face end of the upper housing part (13) and the annular rib (14), there is a sealing ring (15). The motor housing is embodied as a housing pot (26), which with a gripping edge (28) fits over the annular rib (14), sealing ring (15), and part of the upper housing part (13), and is locked to the upper housing part (13), producing an axial clamping force (FIG. 3).