A 60-year-old man presented with impotence ultrasonography demonstrated bilateral irregular hypoechoic infiltration of testes and normal epididymis. Colour Doppler sonography showed only peripheral but no intralesional flow. Since the lesion was presumed as malignancy bilateral high inguinal orchiectomy was performed and bilateral idiopathic granulomatous orchitis was diagnosed. It was concluded that granulomatous orchitis should be considered in the differential diagnosis of diffuse testicular hypoechoic involvement which showed only peripheral low-resistance flow on colour Doppler sonography, in the proper clinical setting. Although this may be a helpful sign in the differential diagnosis of diffuse testicular infiltrations, high inguinal exploration remains mandatory.