A model of the single droplet evaporation of nano-fuel was conducted based on ANSYS FLUENT software with reference to the visualized evaporation experiments. The effects of nanoparticle mass concentration and size on the temperature distribution and fuel-vapor mass concentration during droplet evaporation were discussed. It was revealed by the simulation results that the evaporation equilibrium temperature of droplets tended to rise up with the increasing nanoparticle mass concentration or the size of the diminishing nanoparticle, and the vapor volume fraction was higher during the same evaporation period. At the ambient temperature of 573 K, the temperature inside the nano-fuel droplet was raised by absorbing heat from the external environment. And within the computational domain, the temperature boundary layer and mass concentration boundary layer were formed along the outward droplet surface, which promoted the conversion of liquid to gas. At the initial evaporation of nano-fuel droplet, the vapor volume fraction, as well as the evaporation rate was relatively low, while during the proceeding of evaporation, with the assistance of nanoparticles in enhancing heat and mass transfer, the liquids were evaporated to vapors with increasing rate.