In the slope stability analysis, the polyline slipe surface search is very important. The text will draw back the GA method and the SA unifies, and has displayed the heredity algorithm formidable overall situation search ability, simultaneously used draws back the SA method to strengthen the GA part to ask the fine ability. Through introduction SAGA very good solution landslide most dangerous sliding surface search question, for slope of the sliding surface search provides a new solution method, has overcome conventional method all sorts of malpractices.