Objectives. To determine the connection between polymorphism IL-1B C(+3953/4)T and chronic periodontitis in adults. Materials and Methods. Case and control study. Individuals between 18 and 64 years of age were included; they were recruited through healthcare campaigns carried out in 2012 in different areas of the city of Lima with similar socio-economic characteristics. Dentists specialized in periodontics performed the diagnosis of the periodontal state of participants; genotyping was made through the PCR-RFLP technique. The data were analyzed by logistic regression. Results. The factors associated with chronic periodontitis were: age over 46 years (OR: 7.50, CI 95%: 1.85-6.37), higher education level achieved (OR: 0.43, CI 95%: 0.27-0.98), the presence of allele 2 in the polymorphism of IL-1B. The positive genotype (2-2) was associated with the presence of chronic periodontitis (OR: 2.06, CI 95%: 1.01-4.21). Conclusions. The presence of allele 2 in the polymorphism of IL-1B and the positive genotype (2-2) confers greater risk for the development of chronic periodontitis in the population of Peruvian adults under study.