To weaken the influence of hull deformation on the data of TT&C shipborne outer-trajectory measuring equipments, a hull deformation correction mathematical model is established. The basic structure, measurement principle and measurement elements of hull deformation measurement system are briefly introduced; Then, a hull deformation measurement coordinate system is established,and relationship between deformation measurement angles and Euler’s angles is discussed; Finally, hull deformation data processing formula is deduced in detail and data processing mathematical model is presented. The engineering application results show that the influence of hull deformation on the semi-major axis “a” of spacecraft initial orbit is relatively greater. To near earth and near circular orbit, the influence value is in magnitude of hundred meters, whose maximum value is 800~900 m; and to big elliptical orbit, the influence can reach 20 km. However, the influence can be eliminated after correcting hull deformation. The established mathematical model reflects the objective law of hull deformation, which can be used to eliminate the influence of hull deformation on measurement data effectively and can improve data processing precision.