The invention provides a plasmon photon source device and a method for generating a surface plasmon photon. The method for generating the surface plasmon photon, provided by the invention, comprises the following steps of preparing a layer of graphene on the surface of a dielectric layer to serve as a surface plasmon transmission carrier; preparing a semiconductor layer on the graphene so that the dielectric layer and the semiconductor layer jointly form a waveguide layer of a plasmon photon source to limit a surface plasmon mode; forming a layer of semiconductor quantum dots in the semiconductor layer; and radiating the semiconductor layer with external laser so that a photon radiated by stimulation of the quantum dots is converted to the plasmon photon transmitted in the graphene due to the strong coupling effect of plasmon.