Objective To investigate constitution and costs of inpatients with circulation system diseases in Karamay Central Hospital in 2014 and provide baseline data for further evidence-based pharmacy studies of circulation system single disease. Methods The information of drug use and expenditure of circulation system diseases were collected from the hospital information system (HIS). We analyzed the data of frequency, constituent ratio and cumulative frequency by using Excel 2007 software. Results A total of 2 898 inpatients with circulation system diseases were included. The top three diseases were cerebral infarction, angina and hypertension. The cerebral infarction and coronary heart disease accounted for the largest proportion in the cost. The top one disease of total hospitalization cost, drug expense per capita and inspection cost per capita was cerebral infraction. Conclusion Based on the above results, cerebral infraction and angina were selected as the evidence-based pharmacy study goal of single disease.