Abstract: Accurate model of radiation pressure is essential in determining the variations of the thermospheric density and the winds from accelerometer aboard the GRACE.In order to analyse the radiation model we employed in the paper,modeled radiation acceleration is compared with observed value from accelerometer in radial and cross-track components,which shows that they coincide with each other well.By changing the specular and diffusive reflectivity coefficients in Starboard panel,we observe the change in agreement between modeled acceleration and actual measurement,finding that the reflectivity coefficients in macro-model may be overestimated.By implementing the radiation pressure model inorbit determination with raw macro-model coefficients,the result indicates that the model meets the precision requirement of dynamical orbit determination,making considerable improvement in performance when compared with traditional Knocke model.