In the field of high precision deformation detection, the airborne D-InSAR technique has great potential. Considering the shortcomings of traditional D-InSAR technique, a multi-frequency D-InSAR system is presented in this paper. This method improves the accuracy of detection by reducing the model error, parameter error and data processing error. In this paper, two deformation scenes are tested, compared with the traditional D-InSAR technique, the multifrequency method simplifies the data processing flow and reduces the difficulty of phase unwrapping, meanwhile, the accuracy and stability of the detection results are improved obviously.