In the epitaxial growth of silicon carbide (4H-SiC) by chemical vapor deposition (CVD), the accurate distribution of its temperature field is crucial for the quality of the epitaxial layer. In this paper, the CVD temperature field is simulated and experimentally verified using on-axis 4H-SiC homogeneous epitaxy. It is found that the 3C-SiC crystal polytype inclusions in the on-axis 4H-SiC epitaxial layers are closely related to the temperature field distribution in the growth chamber, and the results validate the simulation results with a high degree of consistency in the temperature distribution between the two, which also verifies the accuracy of the simulation data.To investigate the accuracy of simulations for the epitaxial growth of silicon carbide (SiC) epitaxial layers by chemical vapor deposition (CVD), the homogeneous epitaxial growth of 4H-SiC was experimentally verified using on-axis 4H-SiC substrates. The inverse temperature growth coefficient of the on-axis 4H-SiC epitaxial growth was found to be related to the percentage of 3C-SiC crystal polytype in the epitaxial layers, which is highly consistent with the temperature distribution obtained from the simulation. The validity of the simulation data is confirmed..