Abstract <p>To investigate the effects of jacket strength, thickness, and impact angle on the oblique penetration performance of composite structural rod projectiles, this study employed the AUTODYN finite element software and adopted the single-variable control method to systematically analyze the failure modes, ballistic characteristics, and penetration performance parameters of the rod projectiles under different jacket strengths (Q235, C45, 30CrMnSi), different jacket thicknesses (H/D = 1/7, 2/5, 1), and different impact angles (30°, 45°, 60°). The results show that under oblique penetration conditions, the composite structural rod projectiles exhibit two typical failure modes: “Co-erosion” and “Bi-erosion.” The stability of the failure mode is jointly determined by the jacket strength and thickness. Specifically, the high-strength jacket materials maintain a stable failure mode (all being “Co-erosion”) during oblique penetration, while the low-strength jackets (Q235 and C45) gradually transition from “combined erosion” to “Bi-erosion” as the H/D erosion mode, the “stagnation point” morphology formed the ratio increases. An increase in the impact angle intensifies the asymmetric load effect, prompting the low-strength jackets to undergo “Bi-erosion” earlier. When the composite structural rod projectiles fail in the “separate by jacket increases the asymmetric resistance at the projectile head. This not only causes the penetration trajectory of the projectile to deflect but also increases the penetration resistance of the projectile, thereby impairing its penetration performance. This study provides theoretical support for the structural optimization and engineering application of jacketed rod projectiles in oblique penetration scenarios</p>