This article discusses a 39-year-old pregnant woman who has ovarian hyperstimulation syndrome(OHSS) after artificial reproductive technology, such as asthma, dizziness, hydrothorax, ascites, abdominal fullness, leg pitting edema, dysuria, and so on. Traditional Chinese medicine diagnosed it as water overflowing due to yang deficiency, and accumulated to phlegm-rheum. After 1 month of treatment with traditional Chinese medicine, most of the symptoms were relieved, in addition, hydrothorax and ascites decreased; furthermore, ovary swelling was also relieved. We use this case to discuss possible mechanism and thinking process of traditional Chinese medicine treatment for ovarian hyperstimulation syndrome.