To determine the possible associations of medical status and physical fitness with periodontal disease, a cross-sectional study was conducted. The subjects were 517 males and 113 females aged 23 to 83 years who participated in a multiphasic health test at the Aichi Prefectural Center of Health Care, Japan, from 1992 to 1997. Their periodontal status was assessed by means of the CPITN scoring system. To assess the strength of associations between the examined factors and the score, odds ratios were computed using ordinal logistic models. Conventional risk factors such as old age, smoking habits, and higher fasting plasma glucose and simplified debris index increased the risk of periodontal disease. Hypertension, hematuria, leucocytosis or thrombocytosis, positive C-reactive protein and higher serum alkaline phosphatase were positively associated with the score, whereas higher serum high-density lipoprotein cholesterol was related to a lower risk. Poor physical fitness affecting aerobic capacity, foot balance and reaction was associated with a higher CPITN score. These associations were independent of the conventional risk factors. Although these new potential risk factors should be further investigated for their causal relationship, our findings suggested a close relationship of oral health to medical status and physical fitness.