Objective? Studying influence the risk factors of gestational diabetes mellitus, to provide references for their clinical diagnosis and treatment. Methods A retrospective analysis of the basic datas of 420 pregnant women with prenatal examinationun at The Sixth People's Hospital of Chengdu from March 2019 to March 2021. The pregnant women were divided into diabetic group (210 cases) and non-diabetic group (210 cases) according to the results of the oral glucose tolerance test (OGTT) at 24 to 28 weeks of pregnancy. The general datas ofpregnant women in the two groups were collected and univariate analysis was performed, the factors which had statistical significance in the univariate analysis were fit into the multivariate Logistic regression analysis, and the independent risk factors for gestational diabetes mellitus were screened. Results The results of univariate analysis showed that, the proportion of pregnant women in the diabetes group who were ≥?35 years old, had a family history of diabetes, and the weight growth in early stage of pregnancy, the weight growth in middle stage of pregnancy, serum levels of fasting plasma glucose (FPG), and triacylglycerol (TG), insulin resistance index (HOMA-IR), levels of fasting insulin (FINS), hemoglobin (Hb), albumin (ALB), and alanine aminotransferase (ALT) were significantly higher than those in the non-diabetic group (all P<0.05); the results of multivariate logistic regression analysis showed that, age ≥35 years old, had a family history of diabetes, the weight growth in early stage of pregnancy, the weight growth in middle stage of pregnancy, higher levels of serum FPG, TG, HOMA-IR, Hb, ALB and ALT were all risk factors for gestational diabetes mellitus (OR=1.797, 2.223, 1.687, 2.024, 3.050, 3.086, 5.983, 1.970, 1.992, 2.024, all P<0.05). Conclusion Age≥35 years old, family history of diabetes, the weight growth in early stage of pregnancy, the weight growth in middle stage of pregnancy, higher level of serum FPG, TG, HOMA-IR, Hb, ALB and ALT are all risk factors for gestational diabetes mellitus, corresponding preventive measures can be taken based on the above factors to reduce the risk of gestational diabetes mellitus in clinic.