Abstract: According to characteristics of joint form,base material and plate’s thickness of the long straight main welds on both sides of crane boom,a set of high-quality and efficiency horizontal position laser-MAG hybrid welding solution was put forward,and the corresponding research was carried out. The result showed that the horizontal position laser-MAG hybrid welding technology could reliably and stably achieve one-side welding with back formation of crane boom’s main weld on both sides through the laser keyhole effect,and the weld quality could meet the engineering quality standards. The joint of new experimental scheme was designed to I-type,which did not need beveling process,so that it could reduce the consumption of welding materials and improve the welding efficiency significantly. Compared with the existing technology,one of the greatest advantage of the solution was that it could ensure the back of the weld was fully melted,which could better ensure the size requirements of the front and back of the weld. The other one was that it could achieve single run welding,and that groove processing procedures and workpiece’s turnover procedures were eliminated,so that manufacturing efficiency of the crane boom was improved.