Inflammatory pseudotumor or inflammatory myofibroblastic tumor (IMT) of kidney or perirenal soft tissue is rare benign lesion of unknown etiology, seen mostly in children and young adults. Less than forty cases have been found in the kidney, and less than five cases have been reported in the perirenal tissue. This tumor has been misdiagnosed by pathologists as myxoid leiomyosarcomas, and sarcomatoid carcinomas of kidney in the past. Immunohistochemistry is the key for the diagnosis and urologists should make their pathologists aware of the existence of such condition so that postoperatively benign nature of the condition and good prognosis can be explained to the patient.