The yield of a semiconductor device is improved. Inside the resin sealing body which forms a semiconductor device, the semiconductor chip is sealed in the state where it has arranged aslant to the upper and lower sides of a resin sealing body. In the suspension lead which supports the die pad carrying this semiconductor chip, the small recess is formed in the fifth surface of the opposite side with the surface on which the semiconductor chip was mounted. This recess is a portion used as the starting point when making die pad 2a slanting. The side surface of the side near a die pad between two side surfaces of this recess is formed in the state where it inclined rather than the side surface of the side near the periphery of a resin sealing body.