This work presents the use of limit equilibrium (LEM) and numerical methods by the probabilistic approach, in order to evaluate the stability of an iron ore tailings dam located in Minas Gerais s iron quadrangle. LEM analyzes were carried out using the Simplified Bishop (1955) and Morgenstern and Price (1965) methods, in addition to stress vs strain analyzes with the finite element method. The pore pressure fields generated in the numerical model at two distinct construction stages were exported to the limit equilibrium models in order to guarantee that both analyzes were performed on the same piezometric conditions. For the probabilistic analyzes the FOSM (First Order Second Moment) and Monte Carlo methods were applied. The basic concepts of deterministic and probabilistic stability analysis are presented together with the fundamentals of statistics and probability, FoS (Factor of Safety) calculation methods, as well as numerical modeling concepts. This work also addresses the definition and construction principles of tailings dams. This study presents an application of probabilistic methods to assess the stability of a tailings dam built and heightened by the downstream method. The results indicate that the consideration of a free failure surface was the decisive factor to the magnitude of the influence of each parameter on the PF (Probability of Failure). It was also concluded that the FoS calculation methods had a greater influence on the PF than the foundation s piezometric conditions.