A method of manufacturing a semiconductor device, includes the steps of: (a) providing a support including a plane having a first region for mounting a chip thereon and a second region provided around the first region; (b) forming an insulating resin layer in a semi-curing state on the plane; (c) forming, on the insulating resin layer, a first opening portion for exposing the first region; (d) fitting a chip in the first opening portion to mount the chip on the first region; and (e) completely curing the insulating resin layer after the step (d).