Objective To compare the imaging findings and the clinical value of enlarged iliopsoas bursa (EIB) of ultrasound, CT and MRI. Methods Imaging data of ultrasound, CT and MRI of 100 patients with EIB who were treated in our hospital from January 2016 to June 2018 were collected. All patients were diagnosed by puncture or surgical pathology. The imaging findings and confirmed diagnostic rate of the three examinations were observed. Results Of the 100 patients with EIB, 86 cases were unilateral lesions, including 52 cases in right side, 34 cases in left side and 14 cases in bilateral sides. And the ultrasound showed cystic masses of different sizes, and regular shape of round and oval, flat oval or long eggplant shape, the thin capsule wall and clear edge. The enlarged iliopsoas bursa was round, flat oval and drop-shaped cystic low-density shadow, with different sizes, and adjacent to the pectineal muscle, ending at the level of femoral trochanter under CT. The enlarged iliopsoas bursa was round, flat oval and drip-shaped compartmentalized cystic space, with varying sizes, with long T1 long T2 signal, and high signal in T2WI and significantly high signal in T2WI fat suppression sequences, and its anterior part was iliac vessels, the external part was iliopsoas and the posterior was joint capsule, and it could extend upward or downward. There was a statistically significant difference in the confirmed diagnostic rate of EIB by ultrasound, CT and MRI (P<0.05), and the confirmed diagnostic rate of CT and MRI was significantly higher than that of ultrasound (P<0.05). Conclusion Ultrasound, CT and MRI have their own advantages and disadvantages, and had certain diagnostic value for EIB, and the diagnostic rate of CT and MRI were higher than ultrasound.