A lead frame includes a die pad for mounting thereon a semiconductor chip having a plurality of electrodes, a plurality of leads for electrical connection with the plurality of electrodes of the semiconductor chip, an outer frame disposed on the periphery of the die pad for supporting the die pad and the plurality of leads, and a resin guide portion extending to the vicinity of the die pad from the outer frame for guiding a molten resin over and under the semiconductor chip during resin packaging. A semiconductor device manufacturing method includes mounting a semiconductor chip having electrodes on a substrate having a resin guiding portion for guiding a resin over and under the semiconductor chip during resin packaging; electrically connecting leads on the substrate to the electrodes positioning the semiconductor chip and the substrate between a pair of mold halves injecting a molten resin into the mold and solidifying the resin.