Abstract: To address the problem involving a class of nonlinear networked control systems with controller parameter uncertainties, we simultaneously consider sensor-to-controller and controller-to-actuator packet dropouts and quantization errors, and present an approach for designing a non-fragile quantized H_∞ controller with additive gain uncertainties. Based on Lyapunov stability theory and linear matrix inequality (LMI), we convert the design of the controller with uncertain gain into a convex optimization problem with linear matrix inequality constraints. We then establish sufficient conditions for the existence of a non-fragile robust H_∞ controller in the case of packet dropouts. The proposed controller is robust and non-fragile, and can assure the stability and H_∞ performance of a closed system with a packet-dropout rate, gain perturbation, and quantization density in permitted ranges. Finally, we use a numerical simulation to demonstrate the effectiveness of the proposed approach.