An object of the present invention is to provide a semiconductor device in which peeling between a mold resin and a substrate is suppressed. A semiconductor device 1 includes a semiconductor chip 20 and a substrate 10 that are molded with a mold resin layer 40. The semiconductor device 1 includes a resin layer 50 having a thickness of 200 nm or less different from the mold resin layer 40 between the cured mold resin layer 40 and the substrate 10. The resin layer 50 present between the mold resin layer 40 and the substrate 10 is preferably present on a periphery of 30% or more of the chip when an entire peripheral length of the chip is 100%.