The invention discloses a graphene field-effect transistor linearly doped with a bi-material gate. On the basis of a quantum mechanics nonequilibrium green function theoretical framework, a transport model suitable for the graphene field-effect transistor is built through self-consistent solution Poisson and Schrodinger equation, and further, the influence of a homogenous-material gate and a bi-material heterogeneous gate strategy on electrical properties of the GNRFET (graphene nanoribbon field-effect transistor) is analyzed and calculated by the model. Compared with the electrical properties, such as the output characteristic, the transfer characteristic, the switching current ratio and the like, of the field-effect transistor adopting the bi-material gate, the field-effect transistor adopting a bi-material heterogeneous gate underlap linear doped strategic structure has the larger switching current ratio, and smaller subthreshold amplitude and threshold voltage drift, and namely, the bi-material heterogeneous gate underlap linear doping has a better gate-control capacity, so that a short-channel effect, a band-to-band tunneling effect and a hot carrier effect can be restrained effectively.