Metacognition is people's cognitive activities of self-awareness and self-monitoring, and metacognitive strategy is a self-adjusting learning strategy. The application of metacognitive theory in teaching Advanced English is to use existing cognitive intervention in teaching process. On one hand, it will, more effectively, promote teachers' design of the teaching content and strategies, and real-time monitoring and guidance of students' learning process and effect. On the other hand, it can greatly improve students' learning ability and efficiency, develop students' creative thinking, and improve students' learning methods, so as to further improve the teaching effect.