The purpose of this study was to assess the influence of race, level of education and income on the frequency distribution of periodontal disease in an adult South African population. A retrospective data analysis of the National Oral Health Survey (NOHS, 1988/89) was done on 3,763 adults with an age range of 20-64 years. From the results obtained it would appear that socio-economic variables have an influence on the prevalence of periodontal disease in South Africa.