Total analysis result of inappropriate antibiotic prescriptions of infection specialist are 622 cases, first item is wrong adjust of renal function 498 cases (80.1%), incompatible with culture result and change to narrow spectrum antibiotics 74 cases (12.1), Improper indication25 cases (25%), use more than 3 kinds of antibiotics12 cases (1.9%), Ignore body weight 8 cases (1.3%), prolonguse duration 1 case (0.2%).