According to the field survey of stratum attitude,lithology,tectonic joints at the proposed site area of Wujiang River Bridge,the stability of a giant potential creeping rock mass is analyzed.The result shows that the rock mass is stable as a whole under nature condition.But lubricating zone formed by infiltrating of groundwater,the crustal strongly uplift by the new tectonic movement and cutting cracks all would cause instability of the potential creeping rock mass,which could change the pressure distribution of the bridge piers and causes by locally collapsing and falling at proposed location of Wujiang River Bridge.