Hong Kong International Airport (HKIA) is one of the famous airports built by reclamation of the sea platform. However, the reclaimed area of the airport, which cost about $9 billion, has shown uneven displacement. Over the past two decades, researchers have used different methods to monitor the deformation of HKIA. As an emerging deformation monitoring technology, Interferometric synthetic aperture radar (InSAR), has been widely used to monitoring the deformation of HKIA in the last ten years. In this study, different from conventional interferometry, the target of this interference processing is single look complex (SLC) point data, which was extracted by points in the SLC data stacks (filtered by spectrum and backscatter intensity). We used 40 scenes of COSMO-SkyMed (CSK) SAR images to generate the differential interferogram point data. After multiple phase regression analysis, the SLC point data interferometric processing model can effectively eliminate baseline errors and atmospheric distortions, obtain highly reliable phase unwrapping results.