Within the full linearization framework, the continuous-time observer-based nonlinear control should be determined by solving the implicit, nonlinear ordinary-differential-equation (ODE). To construct the discrete-time nonlinear control, the calculus of finite difference is used such that the finite difference-based output feedback control scheme can be straightforward synthesized since the higher-order difference term is truncated. The nonlinear control methodology with the one-time-delay-ahead prediction effort can ensure the stable output regulation under the specification of nonlinearity bounds. Through the discrete-time Lyapunov function analysis, the presented corollaries show that the sampling time-delay and nonlinearities effects dominate the closed-loop stability and performance. Finally, the proposed control method is successfully demonstrated on an exothermic chemical reactor system with the sampling time-delay and inlet perturbations. (C) 2008 Elsevier Ltd. All rights reserved.