Adipocyte fatty acid binding protein (A-FABP) is a novel adipokine that contributes to the development of cardiovascular disease because of pro-inflammatory properties. Our study aims to evaluate the correlation between serum A-FABP and aortic stiffness in diabetic kidney disease (DKD). Fasting blood samples were obtained from 96 type 2 diabetes mellitus patients with DKD. DKD is identified clinically by persistently high urinary albumin-to-creatinine ratio (UACR) ≥ 30 mg/g and/or sustained reduction in estimated glomerular filtration rate (eGFR) below 60 ml/min per 1.73 m2. Carotid-femoral pulse wave velocity (cfPWV) was measured by using pressure applanation tonometry. cfPWV values of > 10 m/s represented the high aortic stiffness group according to the ESH-ESC 2013. Serum A-FABP levels were determined using a commercial enzyme immunoassay. 53 participants (55.2%) fell under the high aortic stiffness group. This group, compared to the control group, showed higher prevalence of male (P = 0.015), older age (P = 0.025), higher systolic blood pressure (P = 0.001), diastolic blood pressure (P = 0.037), urine albumin-to-creatinine ratio (P = 0.007), serum total cholesterol (P = 0.030), low-density lipoprotein cholesterol (P = 0.043), and A-FABP (P < 0.001). After adjusting for factors significantly associated with aortic stiffness using multivariable logistic regression analysis, serum A-FABP [odds ratio = 1.487 (1.210–1.829), P < 0.001] was found to be an independent predictor of aortic stiffness in DKD patients. Multivariable forward stepwise linear regression analysis also showed that serum logarithmically transformed A-FABP level (log-A-FABP, β = 0.587, adjusted R2 change: 0.426, P <0.001) was positively associated with cfPWV values in DKD patients. In this study, serum A-FABP level is found to be positively correlated with cfPWV values and is identified as an independent predictor of aortic stiffness in DKD patients after adjusting for significant confounders.