Central papillary atrophy and other anomalies of the tongue were studied among 175 diabetic outpatients attending the Tygerberg Hospital. Atrophic lesions of the tongue were found in 26.9% of the patients and 91.7% of these lesions were central papillary atrophy. The degree of control of the diabetes as measured by plasma glucose and urine analyses was not related to the frequency of central papillary atrophy. The prevalence of central papillary atrophy in diabetics was found to be much higher than that of central papillary atrophy and median rhomboid glossitis found in previous investigations among other populations. It is suggested that patients with central papillary atrophy should be screened to rule out diabetes mellitus as the underlying cause. Double central fissures, producing well demarcated triangular areas with their bases at the "sulcus terminalis", were seen in nine instances (5.1%). Four of these areas were associated with central papillary atrophy; the remaining five were covered by non-atrophic mucosa with filiform and fungiform papillae.