The frontier of science and technology has widely entered the era of studying complexity and regulating complex systems.Especially in medicine,research on the complexity of the human system will attract more scholars'and clinicians'attention.Facing the complexity of the human body system directly,this paper applied the definition of complexity,state estimation,and system control models in modern system science to reveal the unique advantages of traditional Chinese medicine(TCM)in understanding human body complexity and regulating human body complex systems.Thus,this paper may not only lay a foundation for dealing with complex diseases in the future but also provides new ideas and methods for forming the future medical model.