Abstract: In order to study the slope stability of open-pit mine, this paper takes a limestone open-pit mine in Sichuan as an example, considering the slope in 3 different working conditions, self-weight+rainstorm, self-weight+rainstorm+blast vibration, self-weight+rainstorm+earthquake. Then the limit equilibrium method and numerical simulation method are used to analyze and study the typical characteristic profile of B zone of the mine, respectively. The result of the analysis show that under the most unfavorable operating conditions（self-weight+rainstorm+blast vibration）, limit equilibrium method show a safety factor of 1.181, numerical simulation method show a safety factor of 1.150, are greater than the allowable factor of safety for slope, indicates that the open slope is a stable slope.