A spring seat is interposed between a spring and a suspension arm supporting the spring. The spring seat includes a support portion for supporting the spring, and an upright partition portion disposed on one side of the spring seat in a lateral direction of the spring seat. The upright partition portion is formed integrally with the support portion for covering a side surface of the spring. The suspension arm includes a recessed portion supporting the spring, and the partition portion has a height equal to or greater than a height of the recessed portion. The partition portion includes a guide surface for upward or laterally guiding foreign matters coming from an outside of the spring seat in the lateral direction of the spring seat.