In general, bloating refers to the subjective sensation of a swollen or distended abdomen, or it may refer to a feeling of abdominal fullness or filling with excess gas, increased intra-abdominal pressure or abdominal wall tension. Abdominal distension is a symptom that is often accompanied by a visible abdominal bulge or an increase in abdominal circumference, and is commonly accompanied by abdominal pain, diarrhea, constipation, nausea, vomiting, and so on. Abdominal distension can be divided into upper, lower and total abdominal distension according to the location; according to the classification of the population, it can be divided into pediatric, female and male abdominal distension. Pediatric abdominal distension can be caused by gas, fluid, mass or abdominal wall muscle weakness in the intestinal cavity, abdominal cavity, etc. Common diseases include congenital megacolon, sepsis, and so on. Female bloating is commonly seen in physiologic bloating during ovulation and menstruation, pelvic inflammatory disease, and can also be caused when ovarian cysts are present. Abdominal distension in men can be seen in prostate hyperplasia, ureteritis, ureteral stones and so on. Once bloating occurs, it is recommended to consult a doctor for a clear diagnosis and targeted treatment.