To handle the problem of variable coupling in Unmanned Aerial Vehicle （UAV） three-axis gimbal stabilization control， an UAV gimbal system control algorithm based on Extended State Observer （ESO） was proposed. Firstly， an attitude solution algorithm model for the desired angle of the UAV gimbal was developed. Secondly， serial PID （Proportional-Integral-Derivative） control loops of position and velocity were constructed. Finally， an ESO was introduced to estimate the angular velocity term online in real-time， which solves the problem that the angular velocity term is difficult to measure directly due to high coupling and multiple external disturbances， and the control input of each channel was compensated. The experimental results show that in scenarios including without command， with command， and composite tasks， the root mean square errors of the proposed algorithm for angle measurement are 0.235 7°， 0.631 7°， and 0.946 3°， respectively. Compared to the traditional PID algorithm， the proposed algorithm achieves angle error reduction rates of 69.43%， 53.29%， and 50.43%， respectively. The proposed algorithm exhibits greater resistance to disturbances and higher control accuracy.