Objective: To investigate the association between IL-1 gene polymorphisms and susceptibility to severe chronic periodontitis and generalized aggressive periodontitis in Chinese Han nationals. Methods: Buccal swabs of DNA samples were collected from 30 patients with severe chronic periodontitis (S-CP), 20 patients with generalized aggressive peridontitis (G-AgP), and 94 ethnically matched healthy control (HC) individuals. Their IL-1A-889/NcoI RFLP, IL1B+3954/TaqI RFLP and IL-1RN intron 2 variable numbers of an 86-bp tandem repeat (VNTR) polymorphisms were analyzed with PCR-RFLP. Results: It was found that all three loci allele 2 frequencies in Chinese population were much lower than those previously reported for European Caucasian populations. The frequency of IL-1B+3954/TaqI allele 2 was significantly higher in the S-CP patient group (P<0.01) and G-AgP patient group (P<0.01) than in the healthy control group, and the frequency of IL-1RN introl II/VNTR allele 2 was significantly higher in the S-CP patient group (P<0.05) than in the healthy control group. Conclusion: IL-1B+3954/Taq I allel 2 and IL-1RN intron II/VNTR allele 2 may be the contributor to the increases susceptibility to severe chronic periodontitis and generalized aggressive periodontitis for some patients. But given the low frequency of allele 2 of both IL-1B+3954 and IL-1RN/VNTR, we believe there must be some other gene loci that may influence susceptibility of Chinese people to periodontitis.