A semiconductor device with a structure in which an increase in the number of oxygen vacancies in an oxide semiconductor layer can be suppressed and a method for manufacturing the semiconductor device are provided. The semiconductor device includes an oxide insulating layer; intermediate layers apart from each other over the oxide insulating layer; a source electrode layer and a drain electrode layer over the intermediate layers; an oxide semiconductor layer that is electrically connected to the source electrode layer and the drain electrode layer and is in contact with the oxide insulating layer; a gate insulating film over the source electrode layer, the drain electrode layer, and the oxide semiconductor layer; and a gate electrode layer that is over the gate insulating film and overlaps with the source electrode layer, the drain electrode layer, and the oxide semiconductor layer.