Objective: To investigate the association of rs5210 in potassium voltage-gated channel subfamily J member 11 (KCNJ11) with gestational diabetes mellitus (GDM). Methods: Six hundred and thirty-two uncorrelated pregnancy females were recruited in Tongji hospital from October 2017 to June 2018, in which 241 pregnant women were identified as GDM, and 391 were non-GDM. All the pregnant women recruited in this study their peripheral venous blood of 5 mL were withdrawn, and DNA in the blood was extracted. rs5210 in KCNJ11 were genotyped using TaqMan Assays and genotype models were analyzed using logistic regression analyses. Results: After adjusting age and body mass index, the variant genotypes of rs5210 in genotype models were as follows: P for dominant model was 0.945, (odd ratio: 0.987, 95% confidence intervals (CI): 0.681-1.430); P for recessive model: 0.556, (odd ratio: 1.217, 95% CI: 0.633-2.343) and P for addictive model was 0.098 (genotype AA vs. GG), (odds ratio: 1.435, 95% CI: 0.936-2.201). Weight-gain during pregnancy and total cholesterol were significantly different in recessive model (P = 0.015, P = 0.022, respectively) of all participants. Conclusion: No significant association between gene susceptibility of rs5210 in KCNJ11 and GDM occurrence in Chinese pregnant women. But the variant of rs5210 was associated with weight-gain during pregnancy and total cholesterol blood levels. However, more cases are needed in genetic study to check its susceptibility with GDM occurrence in Chinese women.