The invention discloses a hydraulic clamp with a bidirectional clamping effect, and relates to the field of hydraulic clamps. The hydraulic clamp comprises a bottom plate, a support seat is fixed at the top of the bottom plate, and a motor is mounted in the middle of the top of the support seat. Through the arrangement of an air exhauster, air inlet pipes, air outlet hoses, buffering air bags, airvalves and exhaust pipes, after a user places a workpiece on a placement frame, the user starts the air exhauster through an operation table, the air exhauster works to enable the air inlet pipes toexhaust air, air enters the buffering air bags through the air outlet hoses to inflate the buffering air bags, after inflation is completed, the user can start an air cylinder to enable a piston rod to extend, then movable rods can be driven to move, clamping plates and the buffering air bags are also driven to move, the buffering air bags move to enable the clamping plates to clamp the workpiece,while when the air cylinder works to enable the piston rod to continue to retract and enable the movable rods to move to apply pressure to the workpiece, the buffering air bags are stressed to be compressed, and therefore, a buffering effect can be achieved on the movable rods and connecting rods.