Disclosed is the invention of a pump dispenser wherein a deformation prevention locking part induces a chaplet to move in the axial direction in a housing at the time of rotation of a head part, thereby allowing or restricting an operation of pressing a head part while preventing the deforming of an elastic member. The disclosed pump dispenser comprises: a cap part fastened to a container; a housing which is provided at the cap part and in which a content stored in the container remains in a dischargeable state; a shaft received in the housing so as to be movable in the axial direction, the shaft including a head part for discharging the content remaining in the housing to the outside through a pressing operation by an external force; a chaplet provided in the housing such that the shaft is inserted so as to be able to extend therethrough, the chaplet allowing or blocking the movement of the shaft on the basis of the angle of rotation of the head part; an elastic member provided on the circumference surface of the shaft and elastically supporting the chaplet and the head part; and a deformation prevention locking part for inducing the chaplet to move in the axial direction in the housing at the time of rotation of the head part, thereby allowing or restricting an operation of pressing the head part while preventing the deformation of the elastic member.