Abstract:The crustal deformation patterns of the North-South Earthquake Belt area from mobile leveling and mobile GPS before Wenchuan Ms8.0 earthquake in Sichuan province are analyzed.The results show as follows. 1) There is a relative uplift area around the epicenter before Wenchuan earthquake measured by mobile leveling, the magnitude of the uplift is more than 180 mm; 2) There is a remarkably compressional deformation showed by mobile GPS observation, which matched with the uplift; 3) It had not any feeling before the earthquake due to some complicated reasons including the first, there are no enough monitoring measures around the epicenter area,so it is difficult to find credible precursors, and the second, we have no any experience and recorded examples about thrust intra-plate earthquake of Ms8 .0.