Considering that it is impossible to implement complete observation to the states of the 3-DOF airborne electro-optical(EO) tracking and pointing platform,we made structural decomposition on the basis of the systems observability.An H∞filter was designed for the observable states of the system.And the designed H∞filter was studied through simulation combined with state feedback H∞stabilization control.The simulation results showed that:When there is uncertainty condition in the noise statistical properties,the H∞filter can observe the system states effectively and achieve better filtering effect with certain robustness.