Purpose: There is growing evidence showing that a number of complex human diseases are caused or are at least influenced by periodontal diseases. Such diseases include cardiovascular diseases, respiratory diseases, diabetes mellitus and ostroporosis. The aim of study was to evaluate periodontal diseases as a risk factor for a preterm low birth weight. Materials and Methods: A total of 48 mothers, 20 of who had a preterm low birth weight delivery, were examined in the Clinics of Periodontology, Faculty of Dentistry, Cumhuriyet University. The periodontal exams consisted of a full mouth pocket depth, a Loe and Sillness Gingival index score measurements, and a panoramic radiograph analysis. Information on any other factors that may cause a preterm low birth weight was obtained from the family physician. Results: The study results indicated that periodontitis (OR: 3.6 95% Cl: 1.06 - 12.18) together with bacterial vaginosis (OR: 11.57 95% CI: 1.26 - 105.7) were independent risk factors of a preterm low birth weight. According to the data obtained from this study, the paternal age, tobacco use and the mothers' height were not significant risk factors for a preterm low birth weight. Conclusion: Within the limits of this study, it is concluded that a poor periodontal health status of the mother may be a potential risk factor for a preterm low birth weight.