Disclosed is an internal and external calibration method used for radiometer imaging. An internal and external calibration system comprises a system frame device (1), a quasi optical device (2), a radiometer array device (3), a radiometer array calibration device (4), a data collector (5), a data processor (6), an electric control device (7) and a display control module (8). Among the devices, a millimeter wave focal plane array imaging technology is employed, radiometers and feed source antenna arrays are utilized to cover a horizontal field of view and reflector mechanic scanning is utilizedto cover a vertical field of view, and the resolution of a near field imaging space is increased through ellipsoidal focusing antennas. Through the radiometer array calibration device (4) among the devices, the effect and the precision of radiometer imaging can be improved firstly in an internal calibration way and then in an external calibration way. Compared with conventional radiometer calibration methods, the method of the invention has the advantages that the testing efficiency is high, great image effects are provided, the precision is high, etc.