Delivery robots have been utilized by many companies to improve service quality and customer satisfaction. One of the challenges in developing delivery robots is designing a trajectory tracking algorithm that controls the vehicle while being subjected to the vehicle’s parameter changes in operation. In this paper, the authors applied an adaptive trajectory tracking controller for a wheeled-mobile robot (WMR) in the presence of uncertain parameters in the kinematic and dynamic models of the WMR. The adaptive nonlinear control law was based on the input-output feedback linearization technique in a multivariable environment to eliminate uncertainty in the system parameters. The results were derived by comparing the adaptive controller with the non-adaptive controller through simulation on MATLAB Simulink. The simulations demonstrate that the adaptive controller not only has significantly lower trajectory tracking error but also greatly improved path-following performance.