Abstract：The contents and meaning of researching visual landslide deductive system are analyzed；and the function and design of a visual deductive system of 3D landslide developed by VC and OpenGL are introduced，which refer to constructing and drawing complex topographic maps，classification and implement of interactive function，etc.. Flexible interactive function is achieved by track-ball algorithm. According to landslide evolution law，the damage process of landslide is divided into five phases. Each phase of landslide is inspected respectively. The characteristic and affect factors of landslide deformation are analyzed；and landslide deformation mechanism is studied. A landslide example of Zigui Jiming Temple shows that the forecasting method by macroscopical phenomena of slope deformation and creep curve of slope displacement with landslide track inspect is practical，and the forecasting result is reasonable.
