The utility model relates to a rigid locking device for an automobile elastic suspension. The rigid locking device for the automobile elastic suspension comprises an automobile elastic suspension mechanism, wherein a frame is elastically connected with an axle through a steel plate spring, a steel plate spring fixing base and bolts to form the automobile elastic suspension mechanism. The rigid locking device for the automobile elastic suspension is characterized in that a rigid locking mechanism is additionally arranged on the automobile elastic suspension mechanism, and a locking component of the rigid locking mechanism controls the frame and the axle to be in the rigid connecting state, or controls the frame and the axle to be in an elastic connecting state through the steel plate spring. The rigid locking device for the automobile elastic suspension has the advantages that the rigid locking mechanism is additionally arranged on the automobile elastic suspension mechanism, a vehicle hydraulic system supplies switching power, and a mechanical structure is used as the locking component; when an engineering vehicle travels at high speed, the frame and the axle are in elastic connection through the steel plate spring, therefore, the buffer action of high-speed traveling is facilitated; when the engineering vehicle is switched to the low-speed operation, a steel wire rope is tensioned, the steel plate spring is pulled up, a link mechanism is pushed at the same time to enable a clamping block to rightly abut against the steel plate spring, the frame and the axle are in the rigid connecting state, and low-speed operation is facilitated.