Objective To assess the impact of atrial fibrillation (AF) on the early outcomes of patients undergoing aortic valve replacement (AVR). Methods The clinical data of 961 adult patients who underwent AVR in Department of Cardiothoracic Surgery, Changhai Hospital between Jan. 2000 and Dec. 2011 were retrospectively analyzed. The patients with pre-operative AF were assigned to AF group (n=54) and the rest to non-AF group (n=907). Pre-, intra-, and post-operative findings were compared to assess the impact of AF on early outcomes. Possible risk factors affecting the early mortality were identified using logistic regression analysis. Results AF patients compared with non-AF patients had an elder age(P<0.001), higher NYHA functional classification Ⅳ(P=0.039), lower left ventricular ejection fraction(P=0.017), and higher proportion of pulmonary hypertension(P<0.001). Accordingly, the post-operative early mortality, mechanical ventilation time, and incidences of low cardiac output syndrome, cardiac arrest/ventricular fibrillation, and acute renal failure were significantly higher in the AF group than those in the non-AF group (P<0.05). Logistic regression analysis showed that age, NYHA functional classification Ⅳ, AF and cardiopulmonary bypass time>120 min were independent risk factors for early mortality. Conclusion AF has a negative impact on the early outcomes of patients undergoing AVR. AF patients have higher post-operative early mortality and more related complications compared with non-AF patients.