Hydraulic jack with lockable top tray and safety device

The utility model provides a hydraulic jack with a lockable top tray and a safety device, which comprises a jack body, a top tray block is mounted at the driving end of the jack body, a plurality of circumferentially arranged connecting blocks are mounted on the jack body, a positioning frame connected with the top tray block is slidably inserted on the connecting blocks, and the top tray block is mounted on the positioning frame. A first locking piece for locking the positioning frame is arranged on the connecting block; a base is installed at the end, away from the top tray block, of the jack body, a plurality of fixing pipes are installed on the base, the fixing pipes are connected with the connecting blocks correspondingly, lifting pieces connected with the top tray block are arranged on the fixing pipes, and second locking pieces used for locking the lifting pieces are arranged on the fixing pipes. According to the hydraulic jack with the lockable top tray and the safety device, the risk that the top tra