In this work, the Sn/g-C3N4 composite was successfully synthesized via a facile chemical reduction method, in which Sn nanoparticles dispersed well on the porous framework of g-C3N4. The composite is used as anode material for Lithium-ion battery, which exhibits significantly improved cycling performance compared to the pure Sn. This result is due to the significant contribution of the g-C3N4 support in preventing volume change during lithiation/delithiation process of Sn.