Objective To investigate the possible relation of miR-30a rs2222722 and its potential target gene SNAI1 rs1543442 mononucleotide polymorphisms to diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (T2DM). Methods A total of 520 patients with T2DM, admitted in the Department of Endocrinology, the First Affiliated Hospital of Chongqing Medical University from October 2018 to September 2019, were included in present study. Of them 240 cases concurred with DKD were set as case group, the other 280 cases non-concurred with DKD as control group. Allele specific TaqMan probe hybridization method was employed to detect the single nucleotide polymorphisms of miR-30a rs2222722 (C>T) and SNAI1 rs1543442 (G>A), and calculate the genotype and allele frequencies of each group. Logistic regression analysis was performed to analyze the independent risk factor of DKD, and the effects of various variables on DKD. Results Among patients with T2DM,the CC genotype carriers of miR-30a rs2222722 were more prone to DKD than the TT and CT genotype carriers (OR=2.73, 95%CI 1.61-4.61, P<0.001). Moreover, the CC genotype was the risk factor of the decreased glomerular filtration rate (OR=2.13, 95%CI 1.37-3.32, P=0.001) and the increased urinary microalbumin/creatinine ratio (ACR) (OR=1.59, 95%CI 1.08-2.34, P=0.019). What's more, the GG genotype carriers of SNAI1 rs1543442 was more prone to DKD than the AA and AG genotype carriers (OR=1.70,95%CI 0.73-1.58, P=0.036). Multivariate logistic regression analysis showed that the miR-30a CC and SNAI1 GG genotype were independent risk factors to the development of DKD. Conclusions The CC genotype of miR-30a rs2222722 and GG genotype of SNAI1 rs1543442 might be the risk factors for the occurrence of diabetic kidney disease. And miR-30a rs2222722 CC genotype is closely related to the decrease of glomerular filtration rate and the increase ACR.