A knee-action-type suspension is provided with an arm member, a compression coil spring, and a shock absorber. The coil spring is extended and retracted between a full-rebound state and a full-bump state in accordance with the magnitude of a load applied to a vehicle body. A wire of the coil spring includes a large-diameter wire portion, a small-diameter wire portion, and a wire diameter varying portion. The large-diameter wire portion is provided in a first portion of the coil spring, which is on the side near to a pivot. The small-diameter wire portion is provided in a second portion of the coil spring, which is on the side far from the pivot. A wire diameter of the large-diameter wire portion is greater than a wire diameter of the small-diameter wire portion.