This paper proposes to design a robust controller for a class of nonlinear networked control systems using aperiodic feedback information. The parameter variation and system nonlinearity are considered as sources of uncertainty. To tackle uncertainty in system dynamics, a linear robust control law is derived using optimal control theory. Two different architectures of closed-loop systems are considered. In the first one, system and controller are not collocated; instead they are interconnected by means of a shared communication network. In the second architecture, however, sensors and controller are connected through a shared communication channel. In both architectures, the feedback loop is closed through the network. To save network bandwidth, the state and input information are transmitted aperiodically through the feedback loop. To this aim, the paper adopts an event-triggered control approach to reduce the transmission overhead. We show that the designed event-triggered controller achieves a trade-off between control performance and saving network bandwidth in the presence of uncertainty. The developed control algorithm is implemented and validated numerically on a classical nonlinear system. © 2020 IEEE.