A semiconductor module includes: a first insulating plate; a second insulating plate is arranged above the first insulating plate; a first semiconductor device provided on an upper surface of the first insulating plate; a second semiconductor device provided on a lower surface of the second insulating plate; an insulating substrate including a third insulating plate arranged between the first insulating plate and the second insulating plate, and a conductor provided on the third insulating plate and connected to the first and second semiconductor devices; and sealing resin sealing the first and second semiconductor devices and the insulating substrate, wherein a withstand voltage of the third insulating plate is lower than withstand voltages of the first and second insulating plates.