Abstract: The modified Stefan-Boltzmann’s law near the general static spherically symmetric black holes is obtained by using WKB approximation. We find that there exists an additive term which is proportional to the square power of the local temperature beyond the leading term in flat spacetime due to spin fields. It hints that the radiation from the black hole may be not exactly thermal.

Key words: Stefan-Boltzmann’s law, General static spherically symmetric spacetime, Spin field.