To provide a radial piston type fluid rotary machine provided with a shoe capable of surely preventing an edge part of the shoe from biting into a cam surface and scratching on the cam surface.

An oil grove 26 is formed on a slide surface 24 of a sliding part 23 touching the cam surface 13, and pressure oil in a cylinder bore 7 is supplied into the oil groove 26 via a communication hole 15 and a through hole 25. A shape in a circumference direction of the slide part 23 is constructed in such a manner that a curvature radius of a part near a front end part 28 and a curvature radius of a part near a rear end part 29 are smaller than a curvature radius of a part near a connecting part with a shaft part 22, the curvature radius gets smaller as it goes to closer to the front end part 28 or the rear end part 29 in the parts near the front end part 28 and near the rear end part 29. Thickness of the slide part 23 in a radial direction is formed in such a manner that thicknesses of the front end part 28 and the rear end part 29 sides are thinner than thickness in a side of the connecting part with the shaft part 22.