to understand the hospital outpatient service don't rational drug use situation, to promote rational drug use. Methods: according to the instructions, clinical pharmacological knowledge and literatures, April 1, 2014 in our hospital outpatient unreasonable drug prescription were analyzed. Results: unreasonable drug prescriptions accounted for 16.89%of the audit prescription; Not rational drug use mainly displays in: medicine and diagnosis, repeated to drugs, dosage form and dosage improper ways: namely interaction or compatibility taboo, etc. Conclusion: under the regulatory role of the relevant departments, in a hospital outpatient prescription medicine rationality gradualy increase, but not rational drug use phenomenon is more serious, should be aimed at the existing problems, formulate corresponding measures, in order to ensure patients' medication safety.