Based on the classical dual-source jamming model, the static tracking error angle of radar seeker under dual-source jamming is briefly explained. On this basis, dynamic attack-defense confrontation is researched, mathematical model and simulation are established, and the attack error is acquired. Missile’s attack trajectory and error are analyzed by simulation, and decoying effect that is influenced by the length between two jamming sources and width of antenna beam when the dual-source power is unequal. Through simulating, as long as the parameters are appropriate, non-coherent dual-source jamming can well decoy radar seeker and protect the target.