Abstract: Objective To investigate the association of monocyte to high-density lipoprotein cholesterol ratio (MHR) and diabetic kidney disease (DKD). Methods A total of 140 patients who presented to the department of nephrology in Nanjing hospital affiliated to Nanjing medical university were enrolled in the study between June 2018 and June 2019. According to the result of 24 h urinary microalbumin, 140 patients with diabetic kidney disease were divided into A1 group (48 patients), A2 group (56 patients) and A3 group (36 patients). Clinical data, including sex, age, serum creatinine, urea, uric acid, triglyceride, total cholesterol, Cystatin C, high-density lipoprotein, low-density lipoprotein, glycosylated hemoglobin, MHR and other indicators as well as whether combined with coronary heart disease, hypertension, were compared between groups. Results The values of TG, Scr, BUN,LDL, MHR levels and the proportion of hypertension and coronary heart disease were higher in the A2 group and A3 groups compared with those in the A1 group (P<0.05). Compared to the A1 group, Scr, BUN,LDL and MHR increased, proportion of complicated hypertension increased, while HDL decreased (P<0.05). Logistic regression analysis suggested that after correction of age, sex, course of disease and blood albumin,LDL, MHR, Scr and hypertension were independent risk factors for diabetic kidney disease (P<0.05). According to the analysis of ROC curve, the area under the curve of MHR was the largest. When the cut-off value was 0.396, the sensitivity was 85.1% and the specificity was 68.8%. Conclusions MHR can be used as a risk factor for progression of DKD. Clinically, the patient whose MHR is over 0.396 needs further related examinations. It is helpful for early diagnosis and treatment of DKD. in order to detect and treat diabetic kidney disease earlier.