Objective To observe echocardiographic characteristics of bicuspid aortic valve (BAV) with Sievers classification.Methods Clinical and echocardiography data of 121 patients with BAV were retrospectively analyzed.According to Sievers classification,the patients were divided into type 0 (no raphe),type 1 (one raphe) or type 2 (two raphes).BAV of type 1 was further divided into three subtypes,including 1(L-R) subtype (the raphe positioned between the left and the right coronary sinuses),1(R-N) subtype (the raphe positioned between the right coronary sinus and non-coronary sinus) and 1 (N-L) subtype (the raphe positioned between the left coronary sinus and non-coronary sinus).The diameters of aorta in BAV patients with Sievers classification obtained with echocardiography were compared.Results There were 3 patients (3/121,2.48％) of type 0 and 118 patients (118/121,97.52％) of type 1 BAV.In patients of type 1 BAV,there were 80 cases (80/121,66.12％) of subtype 1 (L-R),33 (33/121,27.27％) of subtype 1 (R-N) and 5 (5/121,4.13％) of subtype 1 (N-L).There was no type 2 patient among these 121 cases.The diameters of the annulus and sinus of Valsalva in subtype 1 (R-N) BAV patients were less than those in subtype 1 (L-R) BAV (P=0.01,0.02).There was no significant difference of the diameters of the annulus,sinus of Valsalva,sinotubular junction nor the proximal ascending aorta among different subtypes of BAV (all P＞0.05).Conclusion Subtype 1(L-R) is more common in BAV patients,which often associated with larger diameters of annulus and sinuses of Valsalva than subtype 1 (R-N) on echocardiography.