To solve a problem of the difficulty of a tandem arrangement of two radial piston pumps for driving at the same time in parallel in view of its structure and elongation of an axial length.

In this double-row radial piston pump of a tandem arrangement, two sets of selector valve ports perpendicular to each other are disposed on one pintle switching valve shaft disposed at a center part with a certain axial distance, so that the double-row radial piston pump is formed wherein radial type cylinder blocks axially disposed in double-row are inserted. Two eccentric cam rings capable of independently controlling the eccentricity amount and perpendicular to each other are axially arranged in double-row corresponding to the cylinders and the pistons in the respective rows to provide double-row radial piston pump capable of independently controlling a eccentricity amount.