The invention discloses a replaceable impeller for a pump. The replaceable impeller comprises a pump body. An output shaft is arranged in the pump body. A mechanical sealing ring is arranged on the exterior of the output shaft in a surrounding manner. An impeller body is arranged at one end of the output shaft. A first clamping groove is formed in one side of the impeller body. A second clamping groove is formed in one side, away from the output shaft, of the impeller body. A first fixing rod is arranged in the second clamping groove. A limiting rod is arranged on one side of the first fixingrod. A spring is arranged on the bottom of the limiting rod. A second fixing rod is arranged on one side of the spring. According to the replaceable impeller, by arranging the first clamping groove, the second clamping groove, the first fixing rod and the second fixing rod, under the effect of the spring, the second fixing rod can extrude the second clamping groove beneficially, the output shaft is clamped in the first clamping groove to extrude the impeller body, when the impeller needs to be replaced, the second fixing rod can be pushed conveniently, and the impeller can be taken out after the spring is compressed.