To provide a fluid pump restraining fuel from flowing into a clearance between a casing and an impeller and discharging a foreign matter in the flowing-in fuel, smoothly out of the clearance without accumulating it.

Grooves 46 extending outward from the inside of the upper face 16a of a pump body 16 are formed in an inside region of a first pump passage 30. The outside end of the groove 46 is formed in a position forward in the rotating direction of the impeller from a straight line extending outward in the radial direction of the upper face 16a from the inside end. When the groove 46 collides with the first pump passage 30, the groove 46 is connected to the first pump passage 30.