Objective To observe the influence of catheter ablation of the orifice of pulmonary veins (PVs) using ultrasound energy on hemodynamic parameters and explore the safety and efficacy of ultrasound ablation. Methods Nineteen PVs of six canines received ultrasound ablation, with a preset ablation temperature between 55 ℃-65 ℃, for 60 seconds. Ultrasound ablation catheter was positioned on the orifice of PVs via transseptal approach under fluoroscopic. Selective pulmonary venography was undertaken and the hemodynamic data were measured before ablation? immediately and three months later after the ablation.Results All except one canine completed the experiment. All the PVs got effective electrical isolation, and had no stenosis with pulmonary venography, no significant change in hemodynamic parameters was observed before, immediately or three months later after the ablation. Conclusion Catheter ablation within PVs by ultrasound energy was safe and efficient, it was a useful method to treat focal atrial fibrillation derived from PVs in clinical practice.