To provide a fuel pump with increased pump efficiency.

In a disk-like impeller 30, vane grooves 36 are formed in the rotating direction, and an annular peripheral part surrounding the vane groove 36 is formed on the outside of the vane grooves. Fuel sucked from a fuel inlet formed in a pump cover 20 is boosted by the rotation of the impeller 30 in pressure boosting passages 202, 203 on both sides of the impeller 30 in the thickness direction, and force-fed from a discharge port formed in a pump cover 22. The width of the outer peripheral part of the impeller 30 in the radial direction is set to be 1.3 to 2.2 mm. The interval Ds between the impeller 30 and the pump covers, 20, 22 in the axial direction is set to be 5 to 45 μm. The interval Dr between the impeller 30 and the pump cover 22 in the radial direction is set to be 50 to 300 μm.

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