The invention belongs to the technical field of metal machining jigs, and particularly relates to a metal machining jig with high stability. The metal machining jig comprises a base, wherein a supporting column and a smelting furnace are fixedly arranged at the top of the base, a top plate is fixedly arranged at the top of the supporting column, a sliding plate is arranged at the bottom of the top plate in a sliding mode, a lifting box is arranged at the bottom of the sliding plate, a vertical rod is arranged at the bottom of the lifting box in a sliding mode, a horizontal plate is fixedly connected to the bottom of the vertical rod, a connecting block is rotationally arranged at the bottom of the horizontal plate, a horizontally-arranged transverse rod is fixedly arranged on the connecting block, a column body is fixed at one end of the transverse rod, and movable rods are hinged to the two sides of the column body. According to the metal machining jig, a metal piece can be clamped, manual operation is not needed for clamping and fixing, electric operation is achieved, labor is saved, a fixing structure is stable and firm, the space position of metal can be adjusted, the position can be adjusted remotely, feeding is facilitated, the use quality is improved, smelting machining operation is facilitated, and the safety is improved.