For the dynamic response and the instability of the composite cylindrical shell under explosive loading, many factors may affect the stability behavior of the cylindrical shell. In this paper, three main aspects, i. e. the possible defects in the manufacturing process, the spiral angle and the diameter of the copper wire were investigated. Firstly, the 2-D detailed model of the composite cylindrical shell was established to calculated the dynamic response under explosive loading, in which SPH-FEM coupling algorithm was applied. In order to verify the accuracy of the structural dynamic response by using the SPH-FEM model, the simulation results of the metal epoxy composite sleeve were compared, which demonstrated the reliability and numerical accuracy. Secondly, to evaluate the factors affecting the stability of the composite cylindrical shell, an instability criterion based on the particle velocity history of inner wall of the cylindrical shell was proposed. In this method, the velocity curve of the inner wall of the composite cylindrical shell was divided into three stages, and the time corresponding to the point of the velocity surge in the third stage was taken as the instability time of the composite cylindrical shell. Thus, the compression rate of the structure corresponding to the instability under different conditions could be obtained. The results show that the defects and the diameter of copper wire have great influence on the stability of the composite cylindrical shell, while the spiral angle has little influence. Moreover, in the manufacture process of the composite cylindrical shell, it is necessary to improve the quality as much as possible to ensure the integrity of the copper wire. In addition, the parameter of the copper wire diameter should be considered in the device design and experiment, since the copper wire diameter would directly affect the thickness of each layer of the composite cylindrical shell and the defect distribution of copper wire.