OBJECTIVE： To provide reference for the clinical rational drug use. METHODS：Cross-sectional survey was adopted to statistically analyze the off-label use of inpatient （489 prescriptions） and outpatient prescriptions（466 prescriptions） in our hospital in Jun. 19， 2014. RESULTS： The prescription items and ratios of off-label use in inpatients and outpatients in our hospital were 240， 14.1％ （240/1 704） and 149， 17.4％（149/852）， respectively. The top 4 types of drug off-label use included changing administration frequency， indications， compatibility concentrations of injections and dosage. CONCLUSIONS： Some of off-label use are rational， supporting by kinds of guidelines， expert consensus and literature reporting； while some are irrational， clinic should avoid this kind of irrational use and be strictly controlled by pharmacists. Meanwhile， it is suggested that the drug manufacturers update the instructions timely to provide reference for ensuring safety drug use of patients.