Abstract: As rainfall usually influences saturation line of tailing dam，and saturation line is one of the main factors to affect the stability of the tailing dam.Therefore，to study the stability of tailing dam，the influences of saturation line and precipitation should also be investigated.Based on the saturation line of tailing dam，under four different rainfall modes of the normal water level，5% frequency maximum rainfall in 24 h，2% frequency maximum rainfall in 24 h，1% frequency maximum rainfall in 24 h，three kinds of calculation methods including Sweden arc method，Bishop method，and Janbu belonging to the limit equilibrium method，associated with seep synchronous computation，were employed to analyze the stability of tailing dam.It is revealed that minimum safety coefficient has a linear correlation with precipitation.The greater the rainfall，the less the minimum safety coefficient，and the more unstable tailing dam is.Also，the greater the tailing dam area，the greater the influence of rainfall is.

Key words: Tailings dam, Rainfall, Stability, Numerical calculation