This　paper　presents　a　discrete-time　robust　nonlinear　control　scheme　to　achieve　fast　and　accurate　set-point　tracking　for　servo　systems　subject　to　actuator　saturation　and　disturbances.　The　control　scheme　is　built　on　the　framework　of　composite　nonlinear　feedback　(CNF)　control,　which　implements　a　dynamically-damped　closed-loop　system　to　achieve　a　fast　response　with　low　overshoot.　A　disturbance-rejection　mechanism　is　also　included,　which　adopts　an　extended　state　observer　to　estimate　the　state　variables　and　disturbance　simultaneously　for　feedback　and　compensation.　Practical　application　in　the　position　servo　control　of　a　permanent　magnet　synchronous　motor　is　given　to　demonstrate　the　effectiveness　of　the　proposed　control　scheme.