Abstract: The lug/bolt type structural is widely used in modern civil aircraft structure design. The conventional forward design idea is that the structure design comes first and the strength analysis comes second, which has the problems of tedious iterations, long time consuming and error-prone human calculations. Taking aluminum alloy (7075-T6) lug as an example, this paper establishes a correlation equation between the classical load-bearing capacity, the performance parameters and the structural parameters of the lug through reversal design. By means of the design variables method, a set of parametric design method is formed, which can realize the automatic lug design guided by the demand result mode. The visual program developed by MATLAB and solved by an example show that：this method can quickly solve the relevant parameters of the lug and greatly improve the design efficiency under the given load conditions and target requirements.