Ovarian cancer may lead to pleural effusion, but when it leads to pleural effusion, the pathological stage is stage IVA, and pleural effusion usually does not occur in stage II ovarian cancer. The cause of pleural effusion in ovarian cancer may be metastasis of cancer cells to the pleura or lungs, at this time, carcinomatous pleural effusion may be formed; or in the advanced stage of ovarian cancer, the lack of albumin leads to hypoproteinemia, at this time, the accumulation of fluid in the thoracic cavity may also form pleural effusion. Stage II ovarian cancer mainly manifests as one side or both sides of cancerous tumors, or accompanied by tumor invasion in the pelvis, such as invasion of uterus, fallopian tube, ovary, and other pelvic organs; Stage IV ovarian cancer may present pleural effusion accompanied by positive cytology or metastasis to the liver, spleen, and extra-abdominal organs. When ovarian cancer leads to pleural effusion, it usually manifests as chest tightness, shortness of breath, coughing, etc. It is recommended that the relevant people should be treated according to their specific conditions after timely consultation.