Abstract: In view of specific conditions of some tailings dam，three-dimensional finite element simulation method and the computing of seepage field distribution were adopted to fix the features of 3D seepage line depth of tailings dam under ideal conditions of a generalized model; Through analyzing the structural parameters' sensitivity of the seepage drainage，the main factors for impacting the dam seepage line depth were determined. The simulation showed that under the normal working of each drainage structure in function，the depth of tailings seepage line at tailing sub-dam is 15 m below，which is higher than the required value by the specification.

Key words: Finite element, Three-dimensional seepage model, Seepage analysis