In order to investigate the characteristics of the radiative heat transfer for the orifice plate, a steady model was established on the basis of the basic theory of radiative heat transfer. The radiative heat transfer for diverse temperature differences between the metal plate and enclosure surface was studied, and the radiative heat transfer for the orifice plate was analyzed. Finally, a new simplified equation of the radiative heat transfer of the orifice plate was found and proved to be reasonable and reliable with an experiment.