In order to improve the efficiency and movement stability of the high power hydraulic system and reduce the hydraulic impact and energy loss, an electric hydraulic joint valve was designed. The opening and closing of the confluence valve was controlled by the joint control of feedback pressure in the solenoid valve and the reversing valve. The fluid in the valve flowed bidirectional, so the flow speed range was large and the actuator was fast. The valve structure parameters obtained by traditional calculation, throttling groove was designed as U groove, and groove flow area was calculated in Matlab. The AMESim model of the electrohydraulic confluence valve was established and simulated, and the simulation results showed that the flow range of this valve was 0~5.83×10-3m3/s, and the flow rate was stable; in 8~11.5mm spool displacement range, the pressure loss of the confluence valve was decreased with the opening of the valve. When the spool displacement was 11.5mm, the pressure loss of the confluence valve was only 0.18MPa, and the energy loss was small. The test results of the hoisting system of crane showed that the maximum flow rate of the valve was 6×10-3m3/s, and the pressure loss at the maximum flow rate was 0.27MPa. In single pump mode when the hoist was lifted, the minimum stable fretting speed of the reel was 1.9r/min, the starting impact was 2.1MPa, the stop impact was 2.2MPa, the starting delay was 0.7s, and the stop delay was 0.8s; when the hoist was fallen, the minimum stable fretting speed of the reel was 2.17r/min, the starting impact was 5.2MPa, the stop impact was 1.9MPa, the starting delay was 1.1s, and the stop delay was 0.75s. In double pump mode when the hoist was lifted, the minimum stable fretting speed of the reel was 2.17r/min, the starting impact was 2.5MPa, the stop impact was zero, the starting delay was 0.65s, and the stop delay was 0.28s; when the hoist was fallen, the minimum stable fretting speed of the reel was 1.57r/min, the starting impact 〖JP2〗was 2.7MPa, the stop impact was 1.6MPa, the starting delay was 0.57s, and the stop delay was 0.31s.