The invention discloses a pilot valve of a flow path switching valve. The pilot valve comprises a valve body, a valve base is arranged on the front side of an inner cavity of the valve body, a core iron is arranged on the rear side of the inner cavity of the valve body, a connector is formed in the valve base, a sliding block is arranged on the valve base in a sliding manner, the sliding block is connected with the core iron through a drag frame, and when the core iron moves front and back, the sliding block is driven to slide on the valve base to open or close the connector; a vertical through hole is formed in the front side of the drag frame, the sliding block is positioned in the through hole, and runner grooves are symmetrically formed in the sealing face side of the sliding seal of the sliding block and the valve base and the opposite side of the sealing face. According to the pilot valve, mounting of the sliding block is facilitated, meanwhile, the whole performance of a control valve can be improved, implementation is easy, operation is convenient, the production technology of the sliding block is not required to be changed, material investment is reduced, and the production cost is reduced.