The invention provides an automatic welding production line for wire coils. The production line comprises a feeding and conveying mechanism, a pressing and positioning mechanism, a transferring manipulator, a welding manipulator, a discharging and conveying mechanism and a control mechanism in signal connection with the feeding and conveying mechanism, the pressing and positioning mechanism, the transferring manipulator and the welding manipulator. The production line is simple in structure, high in welding speed and high in welding quality stability, the phenomenon that welding of welded junctions is not uniform because of manual welding can be effectively avoided, and therefore welding efficiency, welding precision and welding quality of the wire coils can be improved. The invention further provides an automatic welding method for the wire coils. The method includes a feeding procedure, a transferring and positioning procedure, a welding procedure and a discharging procedure which are all performed in sequence, wherein in the transferring and positioning procedure, the transferring manipulator is controlled to clamp, move and overturn the wire coils, meanwhile, the pressing and positioning mechanism is used for pressing, positioning and rotating the wire coils, and the welding procedure starts. The method can be used for solving the problem that the automation degree in the current welding industry is low.