Feeling something moving on the left side of the stomach may be gastrointestinal gas, caused by a variety of ascites, abdominal distension, etc. The main cause is bad habits or emotional stress, and may also be caused by specific foods. If there is something moving in the stomach during pregnancy, it is considered to be caused by the movement of the fetus, another may be normal bowel movement, which is normal, if there is any other physical discomfort need to go to the hospital for ultrasound examination, clear symptomatic treatment. In addition, the stomach has something moving may refer to intestinal peristalsis, intestinal peristalsis refers to the intestines like worms peristalsis, through the contraction of the movement of digested food downward, can eat coarse fiber foods, such as vegetables and fruits, can accelerate intestinal peristalsis. Regular exercise can accelerate intestinal peristalsis, in some pathological conditions, such as hyperthyroidism, intestinal peristalsis will also be accelerated, so the left side of the stomach feels like something moving for many reasons.