The invention discloses a semi-automatic reinforcing mesh welding machine comprising a tray, a guide rail, a welding gantry and a control platform. Reinforcing steel bars to be welded are placed in the tray at intervals according to the requirement of drawings, and the tray slides to the top end of the guide rail. The welding gantry is erected at the top end of the guide rail. A motor driving thetray to move and the welding gantry are both electrically connected with the control platform. The semi-automatic reinforcing mesh welding machine solves the problems that manual binding of a reinforcing mesh is low in efficiency and poor in quality, and an automatic welding machine is high in manufacturing cost, high in fault rate and the like; through the semi-automatic reinforcing mesh weldingsystem adopting manual material arranging and automatic welding, welding of the reinforcing mesh is achieved, the whole semi-automatic reinforcing mesh welding machine is simple in structure and low in manufacturing cost, and the semi-automatic reinforcing mesh welding machine has the feature of occupying a small space; and meanwhile, the welding gantry adopts flexible gantry welding and can achieve automatic infinite positioning, and therefore a better flexibility is achieved.