Polycystic ovary syndrome (PCOS) is associated with the spontaneous development of an aberrant heterogeneous hormonal environment that thought to be related to multiple genetic or environmental factors remain undefined. Previous studies indicated that IL-1a gene C (-889) T, a polymorphism of the gene encoding a protein which involved in various immune responses, inflammatory processes and hematopoiesis, and is associated with PCOS. A total of 205 PCOS patients and 177 healthy controls were included in this study that used PCR-RFLP to detect C (-889) T variant of IL-1a gene. Clinical measures determined previously were included in the SPSS analysis. The results showed that the presence of IL-1a gene C (-889) T polymorphism in PCOS and healthy controls in Chinese women was not significantly different when studying genotype and allele frequencies. (Genotype: chi(2) = 4.62, df = 2, P = 0.10; allele: chi(2) = 1.35, df = 1, P = 0.25). Furthermore, no association was found between metabolic parameters observed and IL-1a genotypes in PCOS patients in this study. In conclusion, IL-1a gene C (-889) T polymorphism does not appear to be risk factor for PCOS in this population of Chinese women.