Abstract: Objective To provide the reference for the control of disease treatment cost by studying the changing rules of average hospital stay time and hospitalization cost in unstable angina pectoris patients(coded as I20.0 in ICD10) admitted to our hospital in the past two years. Methods Data about the cost of drugs and materials in patients meeting requirement were extracted using HIS.The average hospital stay time,total cost,cost structure and other indices were calculated and the routinely-used drugs and treatment measures for the disease were analyzed. Results The average hospital stay time of unstable angina pectoris patients was 8.85 days with a hospitalization cost of about 40,000 each time,and a material cost of 56.06% of the total hospitalization cost.The cost of top-ten expensive drugs including 7 auxiliary drugs accounted for 50.45% of the total drug cost. Conclusion The hospitalization time of unstable angina pectoris patients increases year by year with a considerable treatment cost.Use of high-value consumables is the key to the control of hospitalization cost.The portion of auxiliary drugs is relatively high,which may be due to their irrational use.