In Interferometric Synthetic Aperture Radar (InSAR), prefiltering plays a crucial role in reducing the noise and improving the coherence of the interferometric phase map. This paper proposes an enhanced space-varying wiener prefilter, which improves the filter structure of the space-varying wiener prefilter and can significantly reduce computational effort and enhance the practicality of the algorithm. The proposed prefilter introduces iterative processing to further improve the prefiltering effect. In addition, a band-pass filter is utilized to remove excess noise from the processed prefilter. It is worth noting that the proposed prefilter does not reduce the range spectral of the image while greatly improving the coherence coefficient. To evaluate the effectiveness and practicality of the proposed algorithm, both simulated and real data are used for verification. The results show that the proposed algorithm significantly improves the coherence of the image pairs and enhances the quality of the interferometric phase map significantly.