Small mesenteric lymph nodes are lymph nodes in the mesenteric region that are not significantly enlarged, usually as a CT imaging manifestation. If there are no obvious gastrointestinal symptoms, it is a normal physiologic manifestation, and can be closely followed up and observed. There are a large number of lymph nodes in the mesenteric region, which are generally small in size, and enlargement of these lymph nodes may occur when there is intestinal inflammation, metastasis of malignant tumors, and other conditions. Inflammation of the intestinal tract can cause regional enlargement of the mesenteric lymph nodes, which may subside after the inflammation resolves. Intestinal tuberculosis also causes localized enlargement of small lymph nodes in the mesenteric region, often located around the tuberculous lesion. Malignant tumors of the colon and small bowel are often associated with enlargement of regionally distributed lymph nodes and require refinement of the colonoscopy for further exclusion and surgical clearance of locally enlarged lymph nodes. If there is any abnormality of mesenteric lymph nodes, we should consult the doctor in time and take targeted treatment under the doctor’s guidance after completing the examination and making a clear diagnosis.