To provide a friction transmission belt and a method of manufacturing the friction transmission belt excelling in power transmission property and sound reducing property in both dry travel and wet travel and maintaining its effect over a long period of time.

A V-ribbed belt 1 comprises an elastic body layer including a rubber layer with core wires 2 embedded along the longitudinal direction of the belt, wherein a rib part 6 used as a friction transmission surface is composed of a rubber composition containing 5-50 pts.mass of water soluble polymer with a melting point or softening point of 80C or lower to 100 pts.wt. of ethylene--olefin elastomer.