On the basis of the force screw theory, the relationship between the grasp matrix of multi-fingered dexterous hand and the external force screw is established to investigate the ability of multi-fingered dexterous hand to grasp an explosive. Firstly, a mechanical model of multi-fingered dexterous hand which can grasp an explosive is constructed and the parameters influencing the grasp are determined. Then, with the maximum grasp being the goal, a mathematical model of the grasp is constructed under the constraint of force closure. Finally, through the neural network and optimization methods, the multi-fingered dexterous hand grasping an explosive is simulated, so as to reveal corresponding the relationship between the grasp position and the explosive weight. Thus, the best grasp position is obtained.