Proceeding of the Joint International Symposium on Deformatuon Monitoring. 2-4 November, 2011. Hong Kong. China. Report. There are more than 30 big dams in Yangzi river, which benefit a lot in power generation for China economy. However, it also bring big problem in environment protection. The biggest and most dangerous environment problem is the land slide area 20kilometers before the dams. More than thousands of landslide area in Yangzi river needed to be monitor, but no more than one hundred area were under control. Chang Jiang Spatial Information Technology Engineering Company (CJSITE) had been working on landslide in Yangzi river monitoring for more than 20 years. Until now, tens of land slide area in yangzi river have been monitored by this company with traditional surveying method such as leveling, trigonometrical survey, GPS and so on. Some of the area have been measured for more than 20 years. PS-InSAR turned to be a novel technology for monitoring land slide and land subsidence in the past ten years. Wuhan university and CJSITE cooperated in a project for monitoring land slide area by PS-InSAR technology. This paper use this technology to monitor several land slide area in Yangzi river surveyed by CJSITE. More than 100 Envisat SAR images of this area have been collected, both PS-InSAR and SBAS method will be tested. The precision and possibility of change detection by PS-InSAR technology were testified by the long time surveying results. Considering the water vapor turbulence along the river, time series data will be polluted seriously. The atmosphere effect of this data set will be modeled and removed by time series data processing procedure. The goal of this project was to find a reliable method to monitoring land slide area which will save more labour and money in this field in the future.