the semiconductor device includes a semiconductor chip , a chip mounting portion , a suspension lead , and a plurality of leads . each of the plurality of leads has a first part and a second part , and the suspension lead has a first part and a second part . the first part of each of the plurality of leads and the suspension lead project from the plurality of side surfaces of the sealing body , respectively . parts of the side surfaces of the plurality of leads and the suspension lead are exposed from the plurality of side surfaces of the sealing body , respectively . an area of the obverse surface of the first part of the suspension lead is larger than an area of the obverse surface of the first part of each of the plurality of leads in a plan view .