This paper describes the process of field uniformity calibration of the practical reverberation chamber which has been built in China Academy of Electronics and Information Technology (CAEIT). According to the IEC 61000-4-21 standard, the data which is obtained from the calibration is processed and compared with the IEC standard. In consequence, the advantage that high radiant electric field strength can be generated easily by low input power of reverberation chamber technique is proved through the course