The invention discloses an automatic brick clamping device comprising a support frame, a hydraulic rotation joint, a hydraulic motor, a buffer balance seat, a brick clamping mechanism and a hydraulic control mechanism, wherein the hydraulic rotation joint is suspended on the support frame, the hydraulic motor is fixed on an end cover of the hydraulic rotation joint and drives a valve plug of the hydraulic rotation joint to rotate, a through hole is formed in the lower end of the valve plug of the hydraulic rotation joint, a cross shaft passes through the through hole to be fixed on the valve plug, the buffer balance seat and the brick clamping mechanism are respectively installed on the two ends of the cross shaft, the buffer balance seat comprises a buffer block, a buffer seat, a spring and a balance seat, wherein the center of the buffer block is fixed on the cross shaft, the buffer block is installed in the buffer seat and is supported by the spring in the buffer seat, the balance seat is fixed below the buffer seat, and the brick clamping mechanism is installed on the balance seat. According to the automatic brick clamping device, the structure is simple, the operation is convenient, the clamping is stable, the work efficiency is high, the production efficiency is improved greatly, and the labor intensity is lowered.