OBJECTIVE： To provide reference for standardizing off-label drug use and guaranteeing clinical rational use of drugs. METHODS： 2 400 prescriptions were collected from outpatient department of our hospital during Jan.-Mar. 2016 at regular interval， and then divided into super-indication drug use， out-of-dose drug use， out-of-administration route drug use and out-of-group drug use. The out-of-label drug use were analyzed by reseaching package inserts， domestic and foreign guideline， domestic and foreign literature， MICROMEDEX Health Care Series database. RESULTS： There were 219 （9.1％） prescriptions of off-label drug use， involving 12 drug types and 38 items of off-label drug use. In mainly manifested as out-of-indication drug use （219 prescriptions， 100％）， out-of-group drug use （4 prescriptions， 1.8％）. All off-label drug use were supported by evidence， among which 9 items （23.7％） of off-label drug use were included in MICROMEDEX. Of all the related off-label drugs， Estradiol valerate tabletes （22.8％）， Metformin hydrochloride tablets （17.4％） and Ethinylestradiol and cyproterone acetate tablets （12.3％） were the most common. CONCLUSIONS： All off-label drug use are supported by evidences in outpatient department of our hospital. There are difference in the quality of those evidence. If off-label drug use is necessary in the clinic， it is suggested to fully weigh the advantages and disadvantages and establish related clinical management system and procedure to avoid medical risks and guarantee the safety of drug use.