A three-dimensional steady state CFD model was developed in ANSYS-Fluent CFD solver to analyze heat transfer capability as well as the wall temperature distribution along the lateral walls of thermosyphon. The physical properties of the fluid and other formulations were taken from the literature to perform the analysis. The CFD simulation predicted the temperature and pressure profile of liquid vapor mixture as well as the distribution of temperature over an entire wall of the thermosyphon for various operating conditions like heat transfer rates and inclination angles. The model was also validated with available experimental results.The CFD simulation helped to visualize the steady state wall temperatures over the entire wall of the two-phase closed thermosyphon (TPCT) the first time which is very difficult to find out by experiments. The influence of inclination angle on the wall temperatures distribution of the lateral surface of the thermosyphon was also analyzed. An optimum inclination angle for heat flux and filling ratio was determined by comparing thermal resistances values.