Creep behavior of weak structural plane plays an important role in the creep deformation of rock mass. Water content of the fillings is a significant factor influencing the creep properties of the weak structural plane. A series of shear creep tests on the weak structural plane of sandstone with different water contents are conducted. The curves of the shear creep deformation vs. time under different water contents of the fillings are derived. The effects of water content on the shear creep behavior of weak structural plane of sandstone are analyzed. Based on the test results

the creep model of the weak structural plane is identified; and Burgers model is derived to describe the creep behavior of the weak structural plane. Moreover

the influences of water contents on the parameters of the creep model are further studied; and the creep mechanism of the weak structural plane of sandstone under different water contents of the fillings is presented.