Abstract: Objective To study the relationship between air pollution and gestational diabetes, and to suggest air pollution as a risk factor for gestational diabetes.Methods The data of glucose oral glucose tolerance test of 4941 pregnant women from Guangdong Women and Children Hospital during 2015 and 2016, and the data of air pollutants (PM_2.5, PM₁₀, SO₂, NO₂) were collected at the same time. The relationship between air pollution and glucose tolerance was analyzed by logistic regression analysis.Results Multivariate logistic regression analysis revealed that PM_2.5= (39.43-48.51) μg/m³ (RR=1.212, 95% CI: 1.041-1.537),> 48.51μg/m³ (RR=1.298, 95% CI: 1.031-1.603), PM₁₀= (56.72-69.36) μg/m³ (RR=1.273, 95% CI: 1.071-1.689),> 69.36μg/m³ (RR=1.359, 95% CI: 1.086-1.777), NO₂= (45.81-49.07) μg/m³ (RR=1.271, 95% CI: 1.093-1.671),> 49.07μg/m³ (RR=1.366, 95% CI: 1.125-1.728), SO₂> 17.13μg/m³ (RR=1.262, 95% CI: 1.003-1.507) were the risk factors of gestational diabetes.Conclusion PM_2.5, PM₁₀, SO₂, and NO₂ can affect blood glucose levels during pregnancy and are risk factors for gestational diabetes mellitus. Therefore, pregnant women should try to avoid the seriously polluted environment, which can reduce the impact of air pollution on the blood glucose levels.