This study was dealt how to solve the problem of analyzing one dimensionalunsteady state heat conduction in semi-infinite rod at constant thermal conductivity.The problem geometry and meshing were made in ANSYS Workbench. Themathematically model was applied on the basis of Fourier’s law. The model wasanalyzed by ANSYS CFX 12.0 solver. The parameters of the model were employed forthe solution for semi-infinite rod with heat generation sources as well as laminar heattransfer coefficient, which was h=14.52 W/m2k. The result findings showed that thereis a significant similarity between the experimental and numerical value. The residualaverage at x1 distance showed the lowest value with highest coefficient sensitivity,which was close to the 0 value. Consequently, this study suggests that the usage ofANSYS CFX 12.0 solver can be used to accomplish the difficulty of analyzing onedimensional unsteady state heat conduction.Keywords: ANSYS, one dimensional heat transfer, rod, heat transfer coefficient.