Abstract: An unsaturated clay slope, with multi-sloping angles, successively consists of loose layers of unsaturated clay, strongly weathered sandstone intermingled by mudstone, moderately weathered sandstone as well as lightly weathered sandstone. The slide interfaces were determined by geophysical approaches and the original slope was reconstructed. The sub-slope masses were classified based on the varieties of sloping angle. A force recursive principle was used to calculate the stability coefficient of the sub-slope masses. The influencing factors such as sloping, water content, cohesion, internal frictional angle, hydrostatic pressure, seismic force as well as train load were analyzed. The step length, range and correlation of the above-mentioned factors were discussed and coupling equations were established to reflect the relationships between density, cohesion, internal frictional angle and water content, as well as the relationship between internal frictional angle and cohesion. The sensitivity of the slope stability was analyzed and susceptive factors were determined when the above-mentioned factors were taken as independent and dependent respectively. The results show that internal frictional angle, cohesion, sloping and water content are the principal susceptive factors influencing the stability of the slope. It can fade the influencing extent of water content and cohesion to the slope stability if the above-mentioned factors are taken as independent variables without considering their correlation.