This paper is concerned with a class of multidimensional (m-D) systems. It first presents results on stability and componentwise exponential convergence analysis of m-D systems. The comparison principle and the technique of mixed monotone decomposition are used to obtain exponential convergence estimates for the system state. The paper further analyzes the almost state decoupling problem of m-D systems. It is shown that the m-D system state can be almost decoupled by similarity transformations if the system matrices generate a solvable Lie algebra. The solvability condition is simple and can be checked directly from the system matrices.