Research conclusions: It is sure that the main influence factors of the hydrostatical pressure characteristics of the tunnel lining are tunnel radius，structural characteristics of primary support，characteristics of grouting reinforcement and drainage capacity of the tunnel drainage system，and the secondary lining external water pressure can be controlled by adjusting every parameters of the tunnel structure part. With the increasing of the tunnel radius，and the enhancing of the impervious capacity of grouting reinforcement and primary support and drainage capacity of the tunnel drainage system，the lining water pressure is decreasing. When the thickness of the grouting reinforcement less than 8cm，the effect of decreases the lining water pressure is significant，while the permeability coefficient of grouting reinforcement should be matched the permeability coefficient of primary support and surrounding rock，otherwise，the effect of grouting reinforcement will be affected. This paper analyses influencing factors and changing rules of water pressure upon lining to high hydraulic pressure mountain tunnel that have guiding significance for design of lining，surrounding rock grouting and drainage system.