To provide a lock device for opening a closing a door through the so-called one-touch manipulation in which the door can be opened only by pushing the door, which can enhance its durability while can be smoothly operated, and which can automatically correct an attaching position between a lock body and a receiving seat even though the position is deviated more or less.

A lock device for opening and closing a door, is composed of a box-like lock body casing 5 opened at its front surface, a slider 6 slidable in the lock body casing 5, a pair of pawls 10, 10 pivotally attached at their proximal ends to the front end of the slider 6, a pair of rollers 17, 17 rotatably supported to the lock body casing 5 in the vicinity of the opening, a slider spring member 22 for urging the slider 7 in its advancing direction, a groove 13 formed in one side of the slider 6 and having a hear-like contour shape, a protrusion piece 20 having its one end slide in the groove 13 only in one direction and the other end attached to the lock body casing 5, a protrusion piece spring member 19 for urging the protrusion piece 20 toward the groove 13 an elastic member 24 interposed between the protrusion piece spring member 19 and the lock body casing 5, and a receiving seat 3 having an engaging member 29 which can be clamped by a pair of pawls.