A stock rubber is provided with chopped aramid fibers and chopped polyester fibers blended in the rubber component, which is EPDM. The chopped polyester fibers are longer than the chopped aramid fibers. A transmission V-belt is obtained and molded from the stock rubber. When molding, the chopped aramid fibers and the chopped polyester fibers are oriented in a width direction of a belt body of the V-belt.