Abstract: In order to solve the problem that the over-mass of the drilling arm affects the maneuverability and working stability, the drilling arm of JMZ type airborne anchor drill is studied, and the response surface method is used to optimize the structure. With the size parameter of the drill arm as the design variable, strength and stiffness as the constraint condition, and mass as the optimization objective, the response surface model was established by using the central combination design method, and the influence law of each variable on the maximum equivalent stress, maximum deformation and mass of the drill arm was analyzed. The response surface model was optimized and solved by using the multi-island genetic algorithm, and the optimal parameter combination was obtained. The results show that the cross section size of the inner cylinder of the fixed arm has the greatest influence on the maximum equivalent stress of the drilling arm, and the cross section size of the inner cylinder of the telescopic arm has the greatest influence on the maximum deformation and quality of the drilling arm. After optimization, the strength and stiffness of the drilling arm meet the requirements, the mass of the drilling arm is reduced by 7.83%, and the maximum equivalent stress is reduced by 14.58%.