To explore the association between the IL-6 -174 G/C polymorphism and the risk of basal cell carcinoma (BCC) in a Chinese population, we performed a case-control study involving 265 BCC patients and 341 controls. Genotyping was performed using polymerase chain reaction with sequence-specific primers. The data showed that the GG+CG and GG genotypes were associated with an increased risk of BCC. The G allele increased the risk of BCC. Moreover, stratified analyses indicated the risk was higher in males, smokers, drinkers, and those aged ≥ 60 years. Cross-over analysis confirmed that the combined effects of the GG or CG genotype and environmental factors (smoking and alcohol consumption) contribute to an increased risk of BCC. In addition, the IL-6 -174 G/C polymorphism was related to larger tumors and multiple lesions. These findings indicate that the IL-6 -174 G/C polymorphism is associated with an increased risk of BCC in a Chinese population. This locus is thus a potential diagnostic marker for predicting susceptibility to BCC.