The invention discloses a solenoid valve with long service life. The solenoid valve comprises a valve seat. A buffer chamber is formed inside the valve seat. An outlet pipe communicating with the buffer chamber is arranged on the right side of the valve seat. An inlet pipe is arranged on the left side of the valve seat. The outlet pipe communicates with the buffer chamber by means of a truncated cone-shaped through hole. A screw hole communicating with the buffer chamber is formed in the middle of the upper surface of the valve seat. The valve seat is in threaded connection with a coil framework by means of the screw hole. A coil is wound around the outer surface of the coil framework. A movable iron core is connected onto the inner surface of the coil framework in a sliding manner. A valve element is welded in the middle of the bottom surface of the movable iron core. Slide bars are welded on the bottom surface of the buffer chamber, deviation of the valve element is avoided through cooperation of the slide bars, slide holes and insertion holes in the movable iron core, the service life of the valve element is prolonged, the valve element and the through hole are positioned relatively precisely, the solenoid valve is closed relatively thoroughly, and normal use of the solenoid valve is ensured.