Abstract: In this paper,the theoretic research on multistep amplitude quantization for a solid-state active phased array with irregular subarrays is presented,and the designing principle and approach are given.It is shown that the lower sidelobe level of multi-step amplitude quantized array should be achieved using the fewer number of quantized steps.Especially for the transmitting array,this novel method gives the advantages of reducing the varieties of modules and devisal costs,and is suitable for engineering application.Lastly,an example is put up for validating the method.