PURPOSE: The correlation between sonographic findings and clinical symptoms was investigated in the patients with mesenteric lymphadenitis who had recurrent acute abdomen. MATERIALS AND METHODS: Seventy-eight children with recurrent acute abdominal pain without obvious primary disease were evaluated by sonography. The initial and follow-up sonography were performed in 17 children. The abdomen was divided into 3 areas. The number and size of mesenteric lymph nodes were observed in each zone, and was compared with the clinical findings. RESULTS: In 56(71.8%) of 78 cases, good correlation was seen in the area of the greatest size and number of the lymph nodes in the sonography. Most severe symptom, was seen in the right lumbar area(49 cases) and umbilical area(7 cases). In 17 cases of follow up, 14 cases showed decrease size and number of mesenteric lymph nodes while 2 cases showed increase in size and number of the nodes with aggravated symptoms. CONCLUSIONS: Ultrasonography was useful to detect and localize the enlarged mesenteric lymph nodes. Initial and follow-up sonography showed good correlation between the changes in number and size of the lymph nodes and symptoms.