A segmented ceramic plunger comprises an upper plunger connector, an inner metal pipe, a ceramic plunger body and a first lower plunger connector. The upper plunger connector is connected with the inner metal pipe, the inner metal pipe is sequentially sleeved with a plunger sleeve and the ceramic plunger body, the ceramic plunger body is segmented, an end face washer is arranged in the middle of the ceramic plunger body, the end face washer (8) is in a horn mouth shape, and the vertical included angle between the end face washer (8) and the central line ranges from 35 degrees to 45 degrees. When the segmented ceramic plunger works normally, the segmented ceramic plunger and a metal washer cannot be staggered, the ceramic plunger runs stably in a pump barrel, and no pump blocking problem exists. The effective sealing segment of the ceramic plunger and the pump barrel can be 900 m, and the clearance sealing need is fully met. Compared with a metal plunger, the expansion amount of the ceramic plunger is almost zero, and it can be ensured that the fit clearance of the ceramic plunger and the pump barrel is stable and accurate.