Tunnel lining water pressure problem has been bone of contention for a long time. Relying on Yichang-Wanzhou Railway karst tunnels to research on distribution of linning water pressure on different anti-drainage patterns (the whole block, block combined with drainage and drainage mode). The primary research method was model test and field monitoring. Model test scale was 1∶16, and test apparatus could be applied earth pressure and water pressure. Acquiring the distribution of linning water pressure by model test: the lining water pressure can't discounted and reduced by the grouting ring at the condition of whole block; the lining water pressure reduced significantly and linear decreased as the development of drainage discharge at the condition of block combined with drainage, simultaneously, the better the effect of grouting, the more outstanding the water pressure reduce; the lining still bear a certain degree of water pressure at the condition of drainage. A part of conclusion about distribution of linning water pressure from model test has been verified in field monitoring.