A bush component force detection device detects a component force acting on a cylindrical bush which is inserted into a hole provided in a frame of a vehicle to pivotally support a rod-like member inside thereof. The device includes: a cylindrical inner ring provided between a bush and a hole and mounted on an outer circumferential surface of the bush; a cylindrical outer ring disposed outwardly of the inner ring with a predetermined space from the inner ring and mounted on an inner circumferential surface of the hole; and a sensing unit that is a cylindrical member disposed in the space between the inner ring and the outer ring substantially concentrically to the rod-like member, the sensing unit having one end connected with the inner ring, the other end connected with the outer ring, and strain gauges disposed on an outer circumferential surface of the sensing unit.