Ovarian hyperstimulation syndrome is a self-limiting disease, and most patients can recover spontaneously. Depending on the degree of the disease, the corresponding treatment principles are different. Mild cases require outpatient observation and follow-up, increased water intake, and no special treatment, and generally return to normal within 1 week. Moderate patients need to be hospitalized for observation, mainly bed rest, rehydration therapy and monitoring of urine output, weight and abdominal circumference. In severe cases, patients must be hospitalized and given aggressive treatment, requiring absolute bed rest, monitoring of pulse, respiration, ascites, pleural fluid and fluid intake and output, and avoiding serious complications by correcting electrolyte imbalance, maintaining blood volume, replenishing albumin and expanding volume, and reducing estrogen levels. If patients experience complications such as shock, water-electrolyte disorders, abnormal liver and kidney function, and thromboembolism, they must be actively prevented and treated. Patients with more ascites with severe self-perceived symptoms can be treated with puncture and release of ascites. If serious bleeding occurs from ovarian rupture, surgery is required as soon as possible.