The invention discloses a semi-automatic multifunction electric welding machine, which comprises a worktable longitudinal moving screw, a stander, an elevation worktable screw, a worktable longitudinal moving motor, a longitudinal worktable, a worktable guide pole, an elevation guide rod, an elevation motor, a welding torch, a welding stick feeding motor, an elevation worktable, an elevation worktable guide rod, an elevation worktable motor, an electric appliance control box and an argon arc welder as well as an annular transformer, wherein an original coil is respectively connected with a power supply indication lamp and a fuse plug, and AC7V, AC12V, AC24V, AC36V, AC40V and O power supply output wire are formed on a tap on an auxiliary coil, wherein 7V, 12V and 24V power supply output wires form a DC 12V, DC24V plus and minus output ends through a rectifier, an output wire of the rectifier is connected with a current meter, each output wire is respectively connected with a power supply output terminal and is installed on a panel of a shell, and the panel of the shell is also provided with a power supply indication lamp, a current adjuster and an output selection adjuster.