Preeclampsia is a multi systemic disorder of pregnancy, with the clinical diagnostic features of hypertension and proteinuria. Although the cause of this disorder is still unknown, current concepts of preeclampsia suggest that generalized dysfunction of the maternal vascular endothelium is a central pathogenic feature. Earlier studies have suggested that normal pregnancy requires a shift to a Th2 type of immunity, at least directed towards the fetus and placenta, while some pregnancy complications, such as preeclampsia, could be due to a skewed Th1 type of immunity. Transforming growth factor-?1(TGF-?1) is produced by T regulatory lymphocytes (Tregs),which play an important role in the physiology of pregnancy. We performed an association study between TGF-?1 polymorphisms and preeclampsia.We used RFLP-PCR and ARMS-PCR methods to detect three known TGF-?1 cSNPs among 143 PE and 128 normal control women, such as 29T?C(Leu10 Pro), 74G?C(Arg25Pro) and 788C?T(Thr263Ile), and compared their allele and haplotype frequencies between the two groups of subjects. The genotype and allele frequencies distribution of 74G?C(Arg25Pro) and 29T?C(Leu10 Pro) SNPs show no significant differences.