Research conclusions:(1)Taking into account seepage body force，strain softening of rock mass，dilatancy and lateral pressure coefficient，elastic-plastic mechanics theory is applied to derive distribution laws of stress and displacement of surrounding rock under two-dimension unequal pressure considering seepage，strain softening and dilatancy，and establish relationships between different partition range of surrounding rocks，pore water pressure，strain softening coefficient of rock mass，dilatancy factor and lateral pressure coefficient.(2)The results have shown that pore water pressure，lateral pressure coefficient，strain softening of rock mass and dilatancy have greater impact on the fractured zone than the plastic zone. Considering lateral pressure coefficient，the impact of seepage field，strain softening of rock mass and dilatancy on the plastic zone and the fractured zone of tunnel along the different directions show inhomogeneity. (3)The results provided a theoretical basis for the stability analysis on surrounding rock of tunnel in high water pressure area. And it is practical meaningful for underground engineering like supporting structure design of the tunnel in the high pressure water-rich area and decision of the scope of the pre-grouting works.