Retrospective evaluation of the cardiopulmonary data is the main point in prevention and treatment of the diseases. In this study, it was aimed to retrospectively evaluate the data of 570 client-owned patients (321 dogs and 249 cats) referred to cardiology unit. The clinical findings, electrocardiographic data, echocardiography and blood analyses were evaluated. Acquired heart disease in 214 patients (37.54%), congenital heart disease in 38 patients (6.6%), and diseases affecting the lower and/or upper respiratory tract in 98 patients (17.19%) were found. Dilated cardiomyopathy was the most common acquired heart disease, and patent ductus arteriosus was the most common congenital heart disease in dogs. In cats, hypertrophic cardiomyopathy was the most common acquired heart disease, while tricuspid valve dysplasia was the most common congenital heart disease. It was concluded that clinical findings, physical examination and diagnostic applications should be evaluated together in the diagnosis of cardiopulmonary diseases.