The lesser curvature of the stomach is the side of the lesser curvature of the gastric sinus, including the lesser curvature of the stomach and the pyloric sinus, which is a part of the gastric structure that is susceptible to ulceration and cancer. The lesser curvature of the stomach is the upper edge where the anterior and posterior walls of the stomach meet, and the lower end meets the pyloric sinus, with the lowest point known as the angular incision, which is a distinct anatomical landmark and the boundary dividing the pyloric sinus from the body of the stomach. The pyloric sinus, also called the gastric sinus, is the very bottom of the stomach, and the pyloric sinus contains the pyloric portion of the stomach including the pyloric canal. Since the small curvature of the gastric sinus is located at the very bottom of the stomach, common clinical gastric ulcers, gastric cancer, and tumors tend to occur in this area, which is clinically significant. When patients find that they have stomach distension, stomach pain and other discomforts, they must pay attention to it, and it is recommended to go to the hospital in time for X-ray or gastroscopy to clarify the location of the lesion for treatment.