Using the thermal particles model of the static spherically symmetric black holes, the thermal radiation laws of the black hole are studied. When η takes the value of inherent thickness, the following results can be obtained. For all Schwarzschild black holes, the radiation power are the same, and the radiation energy flux on the event horizon is inversely proportional to the square of the black hole mass. While the radiation energy flux received by the observer far away from the black hole is inversely proportional to the square of the distance between the observer and the black hole. For Reissner-Nordstrm black holes, the radiation energy flux and the radiation power on the event horizon are not only related to the black hole mass, but also the charge of black holes. For fixed values of η, m and Q, the radiation energy flux received by the observer is also inversely proportional to the square of the distance between the observer and the black hole. For extreme Reissner-Nordstrm black holes, the radiation energy flux and the radiation power are all equal to zero.