Abstract：Based on the all data GM(1，1) model of grey system，different modified models are set up in their given order through out the course of metabolism，residual error modified of different rank，and weighted modified. In setting up the model，unequal intervals in the data of the actual measure are considered；and equal intervals of grey system forecasting model are extended to unequal ones. Together with the information of landslide monitored in Lailong Mountain in Fuyang City，the inclinometer B14，which lies in the active slide area and lasts four typical sliding phases，is studied in the course of where the displacement in sliding zone is forecasted and analyzed comparatively by the computational programs of various models. The result of model precision test shows that the residual error of two rank and weighted modified GM(1，1) model can greatly improve the forecasting precision and adjustability.
