The invention discloses a flip-chip welding metal layer structure for an AC-LED (Alternating Current-Light Emitting Diode) chip structure. A metal layer comprises an upper conductive region and a lower conductive region which are correspondingly connected with a positive electrode and a negative electrode of a rectification circuit in the AC-LED chip structure, as well as a non-conductive heat dissipation region between the upper conductive region and the lower conductive region, wherein the widths of the upper conductive region and the lower conductive region are not less than 50 micrometers; at least two of Cr, In, Ag, Au and Su are evaporated on the upper conductive region and the lower conductive region; the thickness of each film is 10-5000nm; and a plurality of metal structures are formed. The metal layer structure can ensure tight bonding of the metal layer of the AC-LED chip structure and a substrate; the problems that a chip and the substrate are bonded insecurely and contacted insufficiently, and false welding appears during flip-chip welding are avoided; the flip-chip welding can be performed on the substrate and the chip in a relatively low temperature environment; circuits and structures of the chip and the substrate are free from damage; stable operation of a flip-chip, a success rate of the flip-chip welding and a yield of an AC-LED are ensured; in addition, the light emitting efficiency, the heat dissipation property and the like of an AC-LED chip can be improved; and the electrical property and the optical property of the AC-LED can be improved.