The utility model relates to an accessory of soldering tin robot especially relates to a location adjusting device of automatic tin soldering machine. A location adjusting device of automatic tin soldering machine, includes angular adjustment mechanism and soldering iron subassembly, angular adjustment mechanism includes fixing base and the arc locating plate that can be connected with the soldering iron subassembly, the fixing base be equipped with can with arc locating plate sliding connection's arc track, still be equipped with the locating hole that can supply the screw to pass on the arclocating plate, during the location, the arc locating plate passes through screw fixed connection with the fixing base. The utility model discloses an arc locating plate that sets up, the soldering iron subassembly can slide along with the arc track of arc locating plate along the fixing base, can change the soldering iron subassembly and for the angle of vertical direction, make the welding position of soldering iron subassembly more accurate, its simple structure.