<p>Plasmonic nanolasers have attracted considerable attention due to their potential applications in biology, optical sources, sensing, and imaging. In this article, we theoretically demonstrate a tunable plasmonic nanolaser based on Au-graphene gain structures. Results show that when the gain exceeds the loss, the amplitude of the electric field is significantly enhanced, and the intensity of the emission spectrum increases rapidly while the linewidth narrows significantly. The shape and size of the Au nanoparticle play a crucial role in determining the laser characteristics. Additionally, the radiation direction of the laser is confined to a small angle due to the elliptical cross-sectional shape of the nanoparticle. Moreover, the lasing properties can be actively modulated by changing the Fermi energy of the graphene. This study opens a new way for the realization of actively tunable nanolasers and provides a new platform for applications in high-quality factor plasmonic nanocavities, sensing, and innovative nanolaser light sources.</p>