This study aimed to investigate the possible association between diabetes susceptibility gene transcription factor 7-like 2 (TCF7L2) and gestational diabetes mellitus (GDM) in a Chinese Han population. A total of 556 GDM patients and 500 Non-GDM were included. Eighteen single nucleotide polymorphisms (SNPs) were evaluated. Fifteen tag SNPs were selected from HapMap CHB database with a minor allele frequency of >0.2 and r(2) of >0.8. Three additional SNPs were also chosen because these SNPs are associated with type 2 diabetes in East Asians. TCF7L2 rs290487, rs6585194, and rs7094463 polymorphisms were found to be significantly associated with GDM. In multivariate analysis, rs290487 genetic variation (OR = 2.686 per each C allele, P = 0.002), pre-BMI > 24 kg/m(2) (OR = 1.592, P = 0.018), age > 25 years (OR = 1.780, P = 0.012) and LDL-C > 3.6 mmol/L (OR = 2.034, P = 0.009) were identified as independent risk factors of GDM, rs7094463 genetic variation (OR = 0.429 per each G allele, P = 0.005) was identified as independent protect factor of GDM. This finding suggests that TCF7L2 rs290487, and rs7094463 were a potential clinical value for the prediction of GDM.