In order to supply a better irradiation service for materials and electronic devices used in the field of astronavigation and nuclear power plant, the distribution of dose rate was theoretically calculated based on the ideal space model meanwhile the distribution of dose rate was measured with interval of 10 cm. It was found that the scat-tering absorption factor was determined to be 0.86 compared with calculated results. With the use of the experimental equation established in this paper the uncertainty of measurement was supplied and relative results were discussed.  Cited