OBJECTIVES: To describe and compare the first hospitalization cost and the readmission cost of Acute Myocardial Infarction (AMI) patients at Beijing urban area. METHODS: Retrospective data on hospitalization of AMI was selected from Beijing urban employees and residents medical insurance database. We randomly selected 10% of patients first diagnosed as AMI during January 2012- December 2012and then followed those patients to September 2013 .1253 patients were identified in our study and then 335 patients(26.7%) reoccurred during the observation period. All information of patient demographic characters, length of stay and clinical costs were collected. The descriptive statistics were used. The costs of 2013 were converted into 2012 year price with discount rate 3.5%.  RESULTS: We analyzed the 335 patients with recurrence of AMI,(mean age 66.14±15.04 years; 82.39% male), among which 100 patients were readmitted to hospital over three times. The median followed time was 14.17(IQR11.35-18.37, mean 14.29±4.68, ) months. The median hospitalization cost was ￥32,148.42(IQR14303.28-68264.97, mean 42,905.99±36,473.35)at the first time,￥29,189.83(IQR12111.81-64323.44, mean 41281.34±34909.03)at the second time, and ￥25,386.72(IQR13751.55-49162.27, mean 34859.87±30294.72) at the third time or more, respectively (p<0.05) . The median length of stay was 11 days (IQR 7-16, mean 13.75±11.34days) in the first hospitalization,11 days (IQR 7-16, mean 13.91±12.67,)in the second hospitalization, and 13 days (IQR 9-19, mean 16.12±12.97days)in the third hospitalization or more ,respectively. (p<0.05) CONCLUSIONS: Patients with readmission took a relatively high percentage of all AMI hospitalized patients and caused heavy cost. Readmissions over three times had lower  cost and longer length of hospital stay than the first and second hospitalization.