The utility model relates to an automobile -used revolving stage of engineering repairing, including hydraulic motor and slewing bearing, hydraulic motor's output shaft has the speed reducer, the output shaft of speed reducer has first gear, the processing of slewing bearing's outer end have with first gear engaged with tooth, slewing bearing passes through the revolute pair and installs on the frame of engineering repairing car, the tooth of slewing bearing outer end with tooth external toothing on the first gear, the revolving stage mesa is installed to slewing bearing's upper end. The utility model provides an engineering repairing car adopts the motor as the power supply, through smooth -going, the simple structure of gear engagement rotary motion, simultaneously for avoiding the gyration swing, installation gyration cushion valve in hydraulic motor for the gyration is steady reliable.