To determine the frequencies of −800G/A (rs1800468), −509C/T (rs1800469) and 869T/C (rs1800470) polymorphisms and their haplotypes in the TGF-β1 gene and their association with preeclampsia in a population of northern México.This case-control study involved 175 preeclamptic and 253 normoevolutive pregnant women. The polymorphisms were genotyped by real time PCR.The allele and genotype frequencies of polymorphisms showed no significant differences between cases and controls; the −800AA genotype had a very low frequency in cases (1%) and controls (0.4%). The TT genotype of the 869T/C polymorphism is a protective factor of severe preeclampsia (OR 0.56, 95% CI 0.32–0.98). The −509C/T and 869T/C polymorphisms were in linkage disequilibrium (D′=.537, p=.009). The most common haplotypes in case and control groups were −800G/−509C/869C, 34.95% and 37.24%, respectively. We found no increased risk of preeclampsia by haplotype.Our results suggest that −800G/A, −509C/T and 869T/C polymorphisms of TGF-β1 gene or their haplotypes are not associated with preeclampsia and that only the TT genotype of 869T/C polymorphism is a protective factor of severe preeclampsia in a population of northern México.