针对一类具有不确定性的非线性相似组合系统，讨论了鲁棒输出跟踪问题·这类相似组合系统的一个显著特点是其标称子系统具有相同的相对度·充分利用相似结构信息，采用坐标变换和变结构控制方法，将其不确定项分为匹配和不匹配两部分进行处理，得到了一类鲁棒控制器以确保系统输出与参考输出间的误差收敛到原点的一个小邻域内且系统状态保持有界·最后的仿真表明了所得结果的有效性· A robust output tracking problem is discussed for a class of nonlinear similar composite systems with uncertainties. A notable feature of such similar composite systems is that their nominal subsystems have the same relative degree. They make full use of similar structure information, Coordinate transformation and variable structure control method, the uncertainties are divided into two parts: matching and non-matching, and a robust controller is obtained to ensure that the error between the system output and the reference output converges to a small neighborhood of the origin And the state of the system remains bounded. The final simulation shows the validity of the result.