In the manufacture of a semiconductor device by adopting a block molding method wherein a semiconductor chip is fixed onto a wiring substrate through an adhesive, the occurrence of a defect caused by flowing-out of the adhesive is to be prevented. The semiconductor device according to the present invention comprises a wiring substrate, the wiring substrate having a main surface, an insulating film formed on the main surface, and electrodes formed on the main surface so as to be exposed from the insulating film, a semiconductor chip fixed through an adhesive onto the insulating film formed on the main surface of the wiring substrate, conductive wires for connecting the electrodes on the main surface of the wiring substrate and electrodes on the semiconductor chip with each other, and a seal member, i.e., a package, which covers the semiconductor chip, the main surface of the wiring substrate and the electrodes, wherein a groove is formed between the semiconductor chip and the electrodes and the seal member and the wiring substrate have side faces cut by dicing. A protruding portion of the adhesive (an insulating resin) stays within the groove without getting over the groove and does not reach the electrodes. The groove is formed by removing the insulating film partially in the full depth direction of the film so as to extend through the film.