A semiconductor device is produced using a lead frame whose size is smaller than a prescribed center area of a semiconductor chip surrounded by its bonding pads, which are connected with electrodes supported by electrode supports and interconnected with outer frames and an intermediate frame of the lead frame via bonding wires. A series of projections and hollows are formed on the outer frames, wherein the electrode supports are interconnected with the hollows of the outer frames respectively. The semiconductor chip combined with the lead frame, is integrally enclosed in a resin under the condition where only the electrode surfaces are exposed to the exterior, thus forming a resin package. Then, the electrode supports locating the electrodes are cut out and partially removed, so that the electrodes are made electrically independent from each other.