Abstract: It is necessary to compress InSAR monitoring results because redundant information will af-fect the efficiency of deformation mechanism inversion.Combining the characteristics of the InSARdatum and necessary post-processing,an algorithm based on important points extraction is proposed inthis paper.This proposed algorithm is simple but has high compression efficiency.Considering that iscontains a variety of errors which affect the reliability of results and the efficiency of compression,arobust filtering modification is adopted.Then,the data compress method combining robust filteringand important points extracting is proposed.A practical example shows that the proposed combinedmethod is effective for improving the compression ratio.