To satisfy the constrain of structure space of flexible trailing edge, the single cable transmission mechanism is designed in this paper. The nonlinear differential equations coupled by the mid-plate and single cable are derived, and the solving approach and the calculational example are given. The results show that the single cable can be actuated any deformation of the flexible trailing edge within the deflection angle between 0° and 20°. The linear relationship between the deflection angle and the driving force is good. So is the deflection angle and the displacement of cable. The pressure load on every limit pulley increases as the deflection angle increases. The maximum pressure load exerted on the limit pulley is about 20％ of the input force.