The invention provides a double-side automatic clamp for welding and relates to a HDMI (high-definition multimedia interface) double-surface automatic welding machine, in particular to a double-side clamp for welding with HDMI plugs. The double-side automatic clamp comprises a base (1) and a cover plate (2), wherein the cover plate (2) is partially fixed on the base (1) and can be opened, a row of die cavities (12) are arranged in the base (1), welding gun holes (3) pass through the die cavities (12) at the cover plate (2) and the base (1) for forming through holes, and the welding gun holes (13) form stripped through holes along the row of die cavities (12). After the structure is adopted, a plurality of plugs are positioned in the die cavities into a row and are pressed by the cover plate to be fixed, so the stable surface-side welding quality of the plugs by an upper welding gun and a lower welding gun can be ensured, and the double-side welding is completed in one step, so the work efficiency is greatly improved.