A typical dynamic range abnormal event of the CINRAD / SA radar digitized receiver is described and the main influencing factors on receiver dynamic range and the expansion of dynamic performance limitations are analyzed, focusing on the dynamic range abnormalities. Through the step by step sub module troubleshooting, the causes of the malfunction of the receiver dynamic range abnormality are diagnosed in detail, and the rapid and accurate positioning procedure of the faulty is discussed to provide references for the troubleshooting of radar digital receiver dynamic range abnormalities.