In modern air combat, the role assignment (e.g., determining who launches and who guides) plays a pivotal role in multi-aircraft coordinated operations, significantly impacting the effectiveness of attacks. To address the issue of role assignment in multi-aircraft coordinated attack missions, this paper proposes a novel two-stage role assignment framework. First, we establish two key quantitative evaluation models— a missile launch advantage model and a missile guidance advantage model—are established to systematically evaluate the capabilities of multiple Unmanned Combat Aerial Vehicle (UCAV), including attack capability, threat assessment, detection, and guidance performance. Subsequently, a hybrid assignment strategy is developed to optimize role assignment by integrating the relative advantages of UCAVs in launch and guidance tasks. The strategy enables real-time dynamic adjustments in response to evolving battlefield conditions. Finally, the proposed assignment method is validated through simulations, demonstrating its effectiveness and real-time performance, which can enhance the efficiency of future multi-UCAV coordinated air combat.