In geotechnical engineering stability analysis, three basic failure modes, i.e. same circle center failure, load failure and unload failure, may be considered for the rock and soil mass based on different stress paths. In normal researches, point safety factor means the point safety factor of the same circle center failure mode. In this paper, the concept of the point safety factor is extended, the point safety factors under different stress paths are analyzed and the equations and expressions of the point safety factors in the stress space are derived.