This paper discusses a robust stabilization problem for class of multi-input and multi-output ( MIMO) discrete-time non-linear systems with both state and control inputs containing non-linear perturbations. The problem is solved via static output feedback and dynamic output feedback, respectively. A unified approach is used to cast the problem into convex optimization involving linear matrix inequalities (LMI), all the controllers can robustly stabilize the systems and maximize the bound on the non-linear perturbations. This paper also extends the output feedback centralized design approach to class of discrete-time MIMO non-linear decentralized systems, both robust static and dynamic output feedback controllers are obtained.