Objective To investigate the correlation of serum level of paraoxonase 1 (PON1) with alterations of cardiac structure in the patients with chronic renal failure (CRF). Methods Eighty CRF patients admitted in our hospital from January 2013 to April 2015 were recruited in this study, and 40 individuals without any renal diseases who took physical examination during the same period served as controls. The serum PON1 level, total oxidation state (TOS), total anti-oxidation state (TAS) and oxidative stress index were measured and analyzed. Echocardiography was carried out to evaluate the heart structure. Results Left ventricular end diastolic diameter (LVDd), left ventricular mass (LVM) and left ventricular mass index(LVMI) were significantly larger in CRF patients at stage 5 chronic kidney disease (CKD) than in controls (P＜0.05). TAS was significantly lower, while oxidative stress index (OSI) higher in CRF patients at stage 5 CKD than in controls (P＜0.05). The serum level of PON1 was negatively correlated with LVM (r＝-0.641, P＝0.033) and LVMI (r＝-0.562, P＝0.029), and as an independent variable, it could enter the linear regression model with LVM (P＝0.013) and LVMI (P＝0.037) as dependent variables, respectively. Conclusion The serum level of PON1 is significantly decreased in CRF patients, and can be regarded as an independent risk factor for cardiac structure.