Analyzing the temperature observation data in Qingshui hot spring and Linxia water temperature observation well in Gansu Province since 2007, we found that there was obvious water temperature anomaly variation in two wells before and after Wenchuan Ms8.0 earthquake on May. 12, 2008. We did the quantitative analysis on water temperature anomaly information of each well by a linear regression method, slope k-value method and subordi- nate function method, and extracted the better seismic anomaly information. These methods have important effect on processing and analyzing earthquake precursor observation data in long trend drift up (down) type, and are a new way to predict earthquake by using water temperature data for the future.