Abstract: In order to resolve the issue of azimuth platform stability depressing, by using the stabilization principle of two-axis two-framework platform, the reason for the stability depressing and the noise caused by secant compensation of azimuth platform were analyzed,which worked in big pitching angle with azimuth gyro of tradition fixing mode. We proposed to install an azimuth gyro and a roll gyro,which were orthogonal, on the azimuth platform to calculate the inertial azimuth angle velocity of line of sight,and realized the controlling method of azimuth stability with big pitching angle. Simulation experiment validates that, the azimuth stability controlling performance of the two-axis two-framework platform with big pitching angle can be advanced and the influence of gyro noise on the controlling performance can be depressed by using the method. Under the same conditions, the peak-to-peak error of azimuth stabilization can reduce form 450 urad to 250 urad.