Background Recent evidence suggests that dietary habits influence the development and severity of periodontitis. The present cross-sectional study evaluated the association between different types and quantity of alcoholic beverage consumption (alone and interacting with smoking) and the probability to suffer from severe periodontitis in the French e-cohort NutriNet-Sante. Methods The study population consisted of 35,390 adults (mean age: 49.04 +/- 13.94 years), who filled oral health questionnaires and completed at least three non-consecutive 24-hour dietary records. Data on type and frequency of alcoholic beverage consumption were obtained from a semi-quantitative self-reported alcohol frequency questionnaire; the daily quantity (g/day) was estimated from the 24-hour dietary records. The probability of severe periodontitis (main dependent variable) was assessed by calculating the modified periodontal screening score (mPESS) from selected questions. Results A total of 7263 individuals (20.5%) presented a high probability of suffering from severe periodontitis (high-mPESS). After adjusting for confounding factors, the frequency of alcoholic beverage consumption was significantly higher among high-mPESS group than their low-mPESS counterparts, especially for hard liquor/spirits (1.9 +/- 1.4 days/week for high-PESS versus 1.6 +/- 1.1 days/week the low-PESS [P < 0.0001]). The mean daily quantity of ethanol was also higher in high-mPESS versus low-mPESS individuals (11.2 +/- 15.6 versus 7.9 +/- 12.3 g/day;P = 0.011). A stronger association with self-report severe periodontitis was noted when alcohol consumption exceeding > 20 g/day for women and > 30 g/day for men was combined with smoking habit (OR = 7.30 [95% CI: 6.1-8.73]). Conclusion The present results support an association between alcoholic beverage consumption and self-report severe periodontitis, particularly when it is associated with current smoking.