Abstract: In this paper.effects of Lode’sangle of stress on the pore pressure development under differentstress condition have been studied.A series of true triaxial test on medium sand,under different stressconditions have been conducted. The results indicate that,under low stress ratio and high stress ratio,the accumulated pore pressure caused by Lode’s angle of stress can reach 15%and 30% of mean normalstress respctively. The pore pressure can also be effected remarkably by stress path.