Rat salivary glands were examined by an indirect immunofluorescence technique using anti-angiotensin II antiserum. Cells reacting with the antiserum were found in the convoluted granular tubules of the submaxillary gland. In view of the previous reports that renin was isolated from the rat submaxillary gland and that cells with a renin-like immunoreactivity were demonstrated in the convoluted granular tubules of the gland, the present study suggests that a set of substances forming the renin-angiotensin system may be present in this gland.