A case of a juxtaglomerular cell tumor (JCT) in a 46-year-old man is r
eported. The tumor, 2.4 cm at its greatest dimension, was incidentally
detected by ultrasonography. Although histological, immunohistochemic
al, and electron microscopic examinations revealed typical features of
a JCT, the patient had no history of hypertension or hypokalemia. Thi
s is the first report of a non-functioning JCT in the literature.