The aim of this study, which was part of the Mini-Finland Oral Health Survey, was to evaluate the effect of smoking on periodontal condition in the Finnish adult population. A representative sample was drawn from the population aged 30 years and over. The total number of subjects was 8000, 90% of whom participated in the clinical examination. Periodontal diagnoses were made according to the modified Periodontal Treatment Need System (PTNS). Information about age, toothbrushing, and smoking habits was collected by personal interviews. When the sample was divided into two groups (with and without periodontal pockets), the overall risk ratio (RR) was 1.39 and was slightly higher for men than for women. A log-linear model was used to study simultaneous associations and interactions between smoking, periodontal disease, and some background factors. In this model, smoking had not significantly affected the periodontal condition.