Doppler, contrast, and two-dimensional echocardiograms of 12 aneurysms of the sinus of Valsalva in 10 consecutive patients were analyzed in order to highlight the diagnostic features. The diagnosis were confirmed by surgical and/or catheterization findings. The aneurysms had ruptured in 7 of 12 (58%). Two-dimensional echocardiography prior to the contrast studies was able to delineate the aneurysms in 7 of 12 (58%). The contrast studies outlined two additional aneurysms. The right aneurysms directed anteriorly and caudally. The noncoronary aneurysms formed an extraneous lumen at the posterior part of the aortic root, mimicking aortic dissection. Doppler examinations showed systolic and diastolic turbulence in five of six (83%) of the right aneurysms rupturing into the right ventricular outflow tract. Color Doppler echocardiography showed a left ventricular diastolic turbulence emanating from the aneurysm in a case with a noncoronary aneurysm rupturing into the left ventricle. It is concluded that the principal Doppler, contrast, and two-dimensional echocardiographic features usually allow a rapid correct diagnosis of sinus of Valsalva aneurysm.