A new case of splenic-gonadal fusion in an 8-year-old boy is reported in which the sonographic findings were highly suggestive to include the condition in the differential diagnosis. A separate mass with medium-level echoes and a homogeneous echo texture, surrounded by a clearly visible echogenic capsule, was found in contact with the lower pole of the left testis. The particular character of this congenital anomaly is emphasized and the pathogenesis, diagnosis, and treatment are discussed.