The concentrations of kallikrein, as measured by specific radioimmunoassay, in pancreatic tissue of normal, alloxan-, and streptozotocin-diabetic rats were found to be essentially the same. In contrast, the levels of kallikrein in the submandibular glands of the diabetic rats were significantly less than that of the normal rats. However, there were no such differences in the levels of acid phosphatase or alpha-amylase. Thus, the experimentally induced diabetic state would seem to involve a specific reduction in submandibular kallikrein.