This article is concerned with the output tracking control problem for a class of nonlinear switched cascade systems under some average dwell-time-based switching laws. Firstly, stabilisation problem of this class of switched systems is considered. Then, the result is extended to the output tracking control problem. Based on the variable structure control technique and the characteristic of the system, the variable structure controllers and the average dwell-time are designed. The effectiveness of the proposed design approach is illustrated with simulation results.