Fiberoptic gastroscopy and colonoscopy have decades of clinical experience, and there has been very promising progress in the diagnosis and microscopic treatment of stomach and colon diseases, but the role of gastroscopy and colonoscopy for small intestine examination is very limited. Capsule endoscopy is an advanced technology newly developed in recent years for gastrointestinal examination, which is safe and painless, and some media reported that “no injection, no pain, swallow a small pill, gastrointestinal investigation all over”. In fact, this is not possible or rather one-sided. So far, the function of capsule endoscopy cannot achieve a reliable examination of the entire gastrointestinal tract because, in principle, the current capsule endoscope is only a rechargeable micro-camera, which, after being swallowed into the digestive tract, advances through the digestive tract’s own peristalsis, enters the small intestine via the pylorus, then reaches the colon and is finally discharged. Because of the passive movement, the capsule endoscope cannot observe all the directions of the stomach in the larger lumen, such as the stomach lumen, and because the peristaltic movement of each person is different, the power of the capsule endoscope is limited (generally can only work for 5-6 hours), and when the capsule reaches the colon, it cannot provide clear images because of insufficient power, while the space of the small intestine is relatively small, which is conducive to Capsule endoscopy clearly displays images, and the general population has a small intestine emptying time of 4-6 hours, and the electricity is sufficient for the camera to work, so at present, capsule endoscopy is mainly used to examine diseases of the small intestine. At present, capsule endoscopy cannot replace the function of gastroscopy and colonoscopy, much less perform microscopic treatment.