Abstract: In this paper,the two calculation methods including M method and finite linear element method(FLEM) of anti-slide pile are improved based on the researches of the predecessors.The similar M method which is a new one to counter the excavation before the anti-slide pile is proposed.The problem of single row anti-slide pile is divided as three types: the first type is that the slope body before pile is not excavated but divorced from pile;the second type is that the slope body before pile is not excavated and is capable of resisting the anti-slide pile;the third type is that the slope body before pile is excavated.The calculation methods are established to every type of the anti-slide pile: the first type of anti-slide pile can be calculated and designed with M method and the FLEM improved in this paper;the second type of anti-slide pile can also be calculated and designed with the same methods but need count the resistant force of slope body before pile to pile;the another type of anti-slide pile can be calculated and designed with the similar M method proposed in this paper and the FLEM.A series of significant results are obtained comparing with practical engineering.For the safe and economy of engineering,the surveys of reinforcing bar stress in the anti-slide pile are praised highly to remedy the inaccurate of the determining of the landslide force and resistant force before pile.These methods proposed in this paper nearly suit every types of slope and it takes advantages of simply and reliably calculating compared with two-dimension and three-dimension finite element method.It is suggested to extensively use and develop these methods.