In view of the need to reconsider the installation design of strapdown inertial navigation system for large ship-borne new array radar, the basic working principle of strapdown inertial navigation system (SINS) is briefly introduced. The attitude measurement system for antenna array of phased-array radar based on single-axis rotation laser gyro SINS is designed. The composition of the system is explained in detail, and the attitude measurement results under integrated navigation are given by simulation test. It is proved that the system can meet the requirement of precise attitude measurement of shipborne phased-array radar.