Using reverse non-equilibrium molecular dynamics method, we study the thermal properties of grain boundary between two alpha-silicon crystal grains with (200) and (220) crystallographic orientations. The interfacial thermal conductance of the grain boundary and thermal conductivity are temperature dependent, leading to increasing/decreasing thermal transport as the temperature is increased. Also, thermal conductivity increased with increasing grain size. The observed decrease in thermal resistance indicates the suitability of silicon as interface materials for high- thermal conductivity material applications and thermal management in micro and nanoelectronic devices.