During freezing sinking, the displacement and affecting factors of deep alluvium frozen soil wall was a technical problem which need to be resolved. Based on designing frozen soil wall in deep alluvium in thousand metre vertical wall, making use of mathematic simulation software of FLAC after selected ten samples from exceeding 400metres depth as calculation model, which the frozen clay creep parameters with finite transformation considered, the maximum radial displacement was obtained. The factors affecting it such as frozen soil thick, height of deep alluvium, segment height, exposure time and excavated radius were utilized. The mathematic formula was acquired with regression analysis through fifty datas, and detected with in-situ measurement data. The result of two types coincids, which indicates it can provide conducting in designing frozen soil wall under similar geoloical projects.