Abstract: In order to analyze the influence of shell grooves on the fragment formation of semi- preformed warhead, the simulation calculation of different working conditions was carried out, and the experimental verification of typical working conditions was carried out. Using ANSYS/LS-DYNA finite element analysis software, the fracture law of fragments under explosive load was studied, and the influence of the shape and depth of transverse and longitudinal grooves on the fragment formation was obtained. The results show that more fragments will be formed when only transverse grooves are used. When only longitudinal grooves are used, rod fragments will be formed. When the transverse grooves and the longitudinal grooves are prefabricated at the same time, the depth of the longitudinal grooves should be less than 20% than that of the transverse grooves, so that fragments of uniform size and controllable quality can be obtained. When the groove shape is "V+V" or "saw tooth (inclined to the starting point) +V", the fragmentation control effect is better. The experimental study on typical working conditions was also carried out. The experimental results are similar to the simulation results, which proves the correctness of the simulation rules.