Abstract: Aiming at the structural design of a new type inertially stabilized platform based on cable differential transmission, the load analysis, frame structure strength and stability checking were studied. According to the load characteristics and working conditions of the platform, the load was divided into inertial load, centroid-offset acceleration load, friction load and environmental load, and then calculated respectively to conduct load synthesis and power estimation. The static and dynamic structural verification was carried out with the azimuth frame taken as an example. The finite element analysis based on the result of load analysis shows that the frame has good static and dynamic characteristics: the deformation during load transferring and frame overload with the carrier are within the allowable range of the system, which meets the design requirements; the first-order inherent frequency of frame structure is 156.04 Hz, much higher than the bandwidth of the servo system. Accordingly the resonance can be avoided and the frame shows high structural dynamic stability.