A cooling system for V-type engine comprises rows of left and right cylinders arranged in V-type and having coolant jackets, respectively. A coolant pump having a pump shaft parallel to a crankshaft is arranged with a V-bank and at a place away from each cylinder in an axial direction of said crankshaft, and coolant jacket inlets are provided on the side of the coolant pump of each cylinder. Alternately, the coolant jacket inlets of the cylinders are opened respectively at one end face in the direction of the crankshaft of a crankcase-forming member, and a distributing exit passage is defined by joint faces of said crankcase-forming member, a pump casing and a pump casing cover respectively.