Hybrid inertial navigation system (HINS) is a novel navigation system, which integrates the advantages of platform INS, strapdown INS and rotational INS. Rotational gimbals and highprecision high resolution optical grating angle sensors are employed in the HINS, which can achieve the selfcalibration of the HINS error parameters without removing it from the vehicle, thus simplifies the ground calibration task and system routine maintenance, and is conducive to the effectiveness of weapon platform and combat system. Aiming at the structure characteristics and typical rotation modes of HINS, this paper conducts the error analysis for the HINS. Then the designing principle and method of the selfcalibration scheme for HINS are given, and a concrete selfcalibration scheme is provided. The verification experiment of the HINS principle prototype was carried out. Experiment results show that the designed selfcalibration scheme can achieve the accurate estimations of the gyro drifts, accelerometer biases, scale factor errors and installation angle deviations using its own rotation mechanism without removing the HINS from the vehicle, and the calibration accuracy could satisfy the requirements of actual engineering. The proposed selfcalibration scheme possesses high theoretical significance and engineering application value.