The design scheme of the classical D-type iterative learning control law depends on the relative degree of the controlled systems. In order to solve this problem and the problems of the gain of relative degree, and of the higher-order differential operation, a first-order D-type iterative learning control design scheme was presented for a class of nonlinear systems with arbitrary higher relative degree based on the dummy model. The main idea of the method was constructing a dummy model with relative degree one and with gain of relative degree that can be designed arbitrary by connecting in parallel with a first-order subsystem for the nonlinear controlled systems with arbitrary higher relative degree. A first-order D-type iterative learning control law was designed based on the dummy model, so that the dummy model can track the desired trajectory perfectly,and the controlled system can track the desired trajectory within a certain error. The simulation example illustrates the feasibility and validity of the presented scheme.