Inflammatory myofibroblastic tumor(IMT),sometimes known as inflammatory pseudotumor,is an uncommon neoplasm. It is a lesion of uncertain etiology that has been reported in numerous anatomic sites. A 44-year-old woman with a history of abdominal fullness sensation presented to our clinic. The abdominal computed tomography scan showed a hypodense tumor in the spleen.FDG PET/CT confirmed abnormal metabolic activity with a dual-phased maximal standard uptake value of 3.2 and 3.8 in the lesion, respectively. The final pathology disclosed splenic inflammatory myofibroblastic tumor. This is the rare report of this kind of tumor featuring increased FDG uptake on PET/CT image.