To probe the stability problem of highway embankment above soft soil foundation, where geotechnical parameters are available, based on the simple circular sliding stability analysis method, the simplified calculation method of reasonable loading berm width and height with considering c and to provide anti-slide torque is deduced; and the Strength Swedish slice method is used for contrastive analysis of the safety factor and sliding face. The results show: the analytical methods of synthetically considering c and is closer to the situation that the internal friction angle of soft subgrade is nonzero. the proposed method is a simplified applicable analysis method.