Objective To summarize the experience of combined application of low and high frequency ultrasound in the diagnosis of acute primary epiploic appendagitis. Methods The clinical data of 130 patients with acute primary epiploic appendagitis confirmed by operation or other clinical examinations were retrospectively analyzed. Results All the 130 patients were found homogenous or heterogeneous solid block in the area of the abdominal pressure point. Four patients were treated by operation and 126 patients were cured by symptomatic supportive treatment. There were no serious complications in all patients. Conclusion Ultrasonography plays an important role in the diagnosis and differential diagnosis of acute primary epiploic appendagitis.