Fetuin-A and osteoprotegerin (OPG) are arterial calcification regulators, which are related to cardiovascular survival in hemodialysis patients. We hypothesized that a balance of these calcification regulators might mediate the progression of left ventricular (LV) diastolic dysfunction in hemodialysis patients. We recruited 63 hemodialysis patients and measured their serum fetuin-A, OPG, arterial stiffness, aortic calcification and echocardiographic parameters, including the transmitral early diastolic velocity/tissue Doppler mitral annular early diastolic velocity ratio (E/E'), and analyzed the relationships between these variables. Fetuin-A levels were significantly and negatively correlated with the ankle-brachial pulse wave velocity (baPWV), aortic calcification score (AOCS), left atrial volume index (LAVI), LV mass index (LVMI) and E/E'. OPG levels and the ratio of OPG to fetuin-A levels were significantly and positively correlated with the baPWV, AOCS, LAVI and E/E'. A stepwise multiple regression analysis revealed that E/E' was independently correlated with fetuin-A levels (β=-0.334, P=0.02), OPG levels (β=0.367, P=0.01) and the ratio of OPG to fetuin-A (β=0.295, P=0.04). Categorizing the patients according to their serum fetuin-A and OPG levels revealed that patients with low fetuin-A and high OPG levels had the highest LAVI, LVMI and E/E' values after adjusting for potential confounders. Serum fetuin-A levels negatively reflected, whereas OPG levels and the ratio of OPG to fetuin-A positively reflected an increase in vascular and ventricular stiffness, leading to the aggravation of diastolic dysfunction. Therefore, based on our results, the balance of the tissue calcification regulators fetuin-A and OPG could mediate the progression of LV diastolic dysfunction in hemodialysis patients.