The invention relates to a packaging structure of a high-current-power semiconductor device and a manufacturing method. The packaging structure comprises a cooling fin, a semiconductor chip, a plastic package body and a chip-holding island, wherein the chip-holding island is connected with the cooling fin; and a third electrode on a back side of the semiconductor chip is welded on a first surface of the chip-holding island. The packaging structure is characterized in that a first electrode on a front side of the semiconductor chip is welded with one end of a first current-conducting metal sheet; a second electrode is welded with one end of a second current-conducting metal sheet; the first surface of the chip-holding island, the semiconductor chip, a welding end of the first current-conducting metal sheet and a welding end of the second current-conducting metal sheet are packaged in the plastic package body; and the cooling fin, a second surface of the chip-holding island, the other end of the first current-conducting metal sheet and the other end of the second current-conducting metal sheet are exposed outside the plastic package body. The current-conducting metal sheets are directly welded with the electrodes of the semiconductor chip as pins, so that the package resistance of the device is lowered; the overcurrent capability of the device is enhanced; the cooling capability of the device is enhanced; the package thermal resistance is lowered; and the package reliability of the device is enhanced.