The fishy smell of the lower body can be smelled when sitting by yourself generally refers to women and is seen clinically in a variety of situations, such as infrequent washing of underwear. In addition, women will also have a certain fishy smell during menstruation because of the outflow of menstrual blood. It is recommended to pay attention to personal hygiene, especially menstrual hygiene, wash the perineum with warm water every day, change underwear regularly, and avoid spicy and stimulating diet, which will generally improve this symptom. In addition to the above, it is also seen in some diseases such as bacterial vaginosis, cervical lesions and urinary tract infections, which need to be treated actively.1. Bacterial vaginosis: It is a special type of vaginitis, which is caused by anaerobic bacterial infection in the vagina. It generally manifests as increased leucorrhea and leucorrheal discharge with a distinct odor that is fishy and smelly, often more pronounced after rinsing with alkaline substances such as soap. Leukorrhea secretions tested with clue cells can lead to a clear diagnosis. For bacterial vaginosis, anti-anaerobic treatment with metronidazole is given, including topical metronidazole suppositories or then combined with oral metronidazole tablets. Sometimes the male partner should also be treated with oral metronidazole tablets to prevent cross-infection. 2. Cervical lesions: including cervical polyps, cervical erosion, cervical precancerous lesions, and even cervical cancer, these cervical lesions have more local exudation. If secondary to anaerobic bacterial infection, it will also manifest as fishy secretions. If these cervical lesions are present, they should be treated accordingly, for example, cervical polyps should be removed and antibiotic anti-infection treatment should be administered after the removal. If there are cervical precancerous lesions or even cervical cancer, surgery and radiotherapy should be given. 3. urinary tract infection: patients with urinary tract infection and other inflammatory diseases of the urinary system, bacterial or fungal infections are likely to feel the fishy smell of urine after urination, and if they do not pay attention to personal hygiene, they will also smell the odor when they are sitting. It is recommended to follow medical advice to use antibiotics for treatment, drink more water daily, urinate more often and pay attention to a light diet.