Abstract: There are more than 30 000 dangerous earth-rock dams in China. Due to long-term service,the mechanical properties of the material of the dangerous earth-rock dam are seriously attenuated and impermeability cannot meet the requirements. There is a greater risk of dam failure. The stability of a dangerous earth-rock dam is an uncertainty problem related to the shear strength of the dam material and the reservoir water level. The traditional reliability analysis method of earth-rock dams does not fully consider the many uncertain factors of the dangerous earth-rock dam,causing the probability of failure to be unable to match theoretical expectations. This paper combines the upper bound theorem,finite element discretization technology,mathematical programming theory with Monte Carlo method,and at the same time uses the shear parameters of the dangerous earth-rock dam material and the upstream reservoir water level as random variables to establish the reliability of the dangerous earth-rock dam. The upper limit method stochastic programming model is analyzed,and the corresponding calculation program is compiled. Finally,a dangerous earth-rock dam in Yunnan is calculated and analyzed,and the failure probability of the earth-rock dam under the design conditions and long-term service conditions is obtained. The research results provide a theoretical basis for the treatment of the dangerous earth-rock dam.