An analytical investigation of a half-car model with passenger dynamics, subjected to random road disturbance, is performed. Two different methods of defining the performance index for optimal controller design are proposed. Nondeterministic inputs are applied to simulate the road surface conditions more realistically. Results obtained illustrate that using an optimal state-feedback controller, with passenger acceleration included in the performance index, would exhibit not only an improved passenger ride comfort, but also, a better road handling and stability.