This paper introduces a novel predictive guidance law for unmanned aerial vehicles (UAV) focusing on active defense scenarios. The optimal predicted interception point is selected based on the analytical solution of constant-acceleration maneuvering envelope. Utilizing a real-time nonlinear predictive model, this guidance law facilitates dynamic responses to attacker threats, allowing for precise interception with minimal guidance miss. The proposed method significantly enhances the interception efficiency by reducing computational demands and improving trajectory accuracy under various operational constraints. Simulations conducted in a MATLAB environment demonstrate the guidance law’s superior performance compared to traditional methods, particularly in handling complex engagement scenarios. The results validate the guidance law’s potential for broader applications in military and civil UAV operations, providing a robust foundation for future research into adaptive guidance systems.