Objective To investigate the effect of radiofrequency catheter ablation (RFCA) on the function and structure of left ventricle during treatment for frequent premature ventricular beats (PVBs). Methods Totally 56 patients with PVBs, who had been successfully treated with RFCA from Jan. 2006 to Dec. 2010, were included in the present study (ablation group). The other 42 patients with frequent PVBs, who received no RFCA treatment, served as controls (non-ablation group). The changes of total number of PVBs, left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), interventricular septal diameter (IVSd), left ventricular posterior wall diameter (LVPWd) were observed before and after different treatments. Results (1)Compared with the non-ablation group, the ablation group had significantly reduced total number of PVBs ([125±113]/24 h vs [17 813±1 542]/24 h, P<0.01), increased LVEF ([0.72±0.06] vs [0.64±0.08], P<0.05), and significantly decreased LVEDD ([44.1±4.0] mm vs [48.9±3.8] mm), LVESD ([27.0±3.7] mm vs [30.1±4.2] mm), IVSd ([7.5±0.8] mm vs [8.5±0.8] mm), and LVPWd ([7.5±0.8] mm vs [8.5±0.9] mm) (P<0.05).(2)Compared with the baseline levels, the total number of PVBs in the ablation group decreased from (23 662±12 559)/24 h before RFCA to (125±113)/24 h(P<0.01) after RFCA,and patients had relieved chest tightness and heart palpitations. Meanwhile, the LVEF was significantly increased after RFCA ([0.72±0.06] vs [0.64±0.09], P<0.05); LVEDD ([44.1±4.0] mm vs [50.6±5.4] mm), LVESD ([27.0±3.7] mm vs [32.1±5.3] mm), IVSd ([7.5±0.8] mm vs [8.8±1.1] mm), and LVPWd ([7.5±0.8] mm vs [8.7±1.1] mm) were significantly decreased after RCFA (P<0.05). Conclusion RFCA can effectively improve the structural remodeling and cardiac dysfunction induced by PVBs, relieving the patient symptoms.