Abstract: Low-power pulsed Nd:YAG laser-TIG hybrid welding process of 2 mm AZ31B magnesium alloy plate was studied.The experiments results showed that the energy cooperation between laser and arc will have influence on the weld appearance HJ1.35mmin laser-TIG arc hybrid welding process.The favorable range of hybrid welding parameters was relatively narrow at high welding speed.In order to get the ideal joint, the back of the specimen should be protected by the Ar gas.When the protective gas flow was 5-10 L/min, the favorable performance can be obtained.The tensile strength of laser-arc hybrid welding joint was 95% of Mg base metal.