Smooth mucosa of the duodenal bulb is not a disease state. The duodenum is between the stomach and the jejunum, starting at the pyloric portion of the stomach and ending at the suspensory ligament of the duodenum, and is about 25 cm long, C-shaped around the head of the pancreas, and is the most fixed part of the small intestine. The duodenal mucosa is the inner layer of the duodenal wall, i.e., the inner tissue that comes into contact with food. Normally, the duodenal bulb mucosa is smooth, and the pathological state of the duodenal bulb mucosa generally includes abnormal morphology, abnormal mucosal color, neoplastic organisms, erosions, ulcers, and bleeding. Therefore, smooth duodenal bulb mucosa is not a disease state. If there are any abnormalities in the digestive tract, you should seek timely medical treatment under the guidance of a professional physician, and should not blindly deal with them on your own, resulting in adverse consequences.