The invention provides a graphene device structure and a method for manufacturing the same, the device structure comprising a graphene layer; a gate region in contact with the graphene layer; semiconductor doped regions formed in the two opposite sides of the gate region and in contact with the graphene layer, wherein the semiconductor doped regions are isolated from the gate region; a contact formed on the gate region and contacts formed on the semiconductor doped regions. The on-off ratio of the graphene device is increased through the semiconductor doped regions without increasing the band gap of the graphene material, i.e., without affecting the mobility of the material or the speed of the device, thereby increasing the applicability of the graphene material in CMOS devices.