This paper deals with the long-term deformation of Mechanically Stabilized Earth (MSE) walls induced by the corrosion of the steel strips that ensure their internal stability. The analysis consists of defining assumptions regarding the spatial variations of the corrosion process throughout the wall, called corrosion scenarios, that define the evolution of the stiffness and strength of the steel strips. This evolution is introduced into finite element simulations of the behavior of a typical wall, in which interactions between the backfill and the strips are considered using a generalized homogenization procedure (called a multiphase model). The results of the simulations are used to discuss the influence of the heterogeneity of the corrosion process on the overall time evolution of the wall.