The fault distributions and reference depths in Longmenshan and adjacent areas before earthquake were obtained by Euler equation (Euler deconvolution) inversion method about gravity data of Wenchuan area. A gravity profile was designed in this area to compare the fault morphology before and after the earthquake. The thrust nature of Longmenshan belt diminished, and a number of fracture zones between Yingxiu-Beichuan fault and Dujiangyan-Jiangyou fault were produced. The viewpoints of stress plane (second earthquake plane) and multi-sources were proposed according to the genesis research about Wenchuan earthquake 2008 through fault morphology differences.