Valvular heart diseases (VHD) occur frequently in Turkey. However, epidemiological studies of VHD have not been completed until now. The aim of this study is to identify the VHD type, clinical, laboratory characteristics, and treatment methods among VHD patients in Turkey.The study was conducted prospectively between June 2009 and June 2011 at 42 centers, and included patients with native VHDs, infective endocarditis, and/or previous valve interventions.All medical data from 1300 patients were recorded. Mean age was 57±18 years and the female/male ratio was 1.5. VHD was native in 84% of patients, 15% had previous interventions, and 1% had infective endocarditis. Among the native VHDs, mitral regurgitation was the most frequent lesion (43%), followed by multiple VHDs (32%). Degenerative etiology (86%) was more frequent in aortic VHD, and rheumatic origin was the main cause in all VHDs. While the prevalence of aortic stenosis increased with age, mitral stenosis decreased with patient age. The most frequent symptom was shortness of breath (73%). Clinical and echocardiographic examinations (54%) were mostly used as diagnostic techniques for determining treatment course. Percutaneous mitral balloon valvuloplasty (PMBV) was performed in 76% of the patients with mitral stenosis and mechanical prosthetic valve replacement was performed in 74% of the patients with other lesions.This study showed that the main cause of VHD is rheumatic fever. Mitral regurgitation and multiple valvular lesions are the most frequent VHDs in Turkey. PMBV and mechanical prosthetic valve replacement are the preferred treatment methods for VHD.