Bloating on both sides of the small stomach may be caused by indigestion, abdominal fluid accumulation, peritonitis and so on. 1. Indigestion: If you suffer from indigestion, you will feel bloated on both sides of your stomach due to the slowing down of gastrointestinal peristalsis and the accumulation of undigested food in the stomach. 2. Peritoneal effusion: Peritoneal effusion is commonly seen in renal disease, cardiovascular disease, liver disease, etc. Patients will have a feeling of distension and tenderness in the abdominal wall, which is usually accompanied by the symptom of edema as well. 3. Peritonitis: Peritonitis is generally secondary to the more common, mainly from the abdominal cavity of the organ infection, necrosis perforation, etc., the patient may manifest abdominal distension, abdominal pain, abdominal muscle tension, as well as nausea, vomiting, fever and other symptoms. It is recommended that the patient seek medical attention in a timely manner, carry out the appropriate examination to clarify the cause, and take appropriate measures under the guidance of the doctor.