OBJECTIVE：To understand the pharmacists’ knowledge for the rational drug use in the elderly， and to provide reference for promoting the role of pharmacists in it. METHODS： A questionnaire was designed according to the Beers Criteria （2012 edition） to investigate the situation of pharmacists’ （who were from some third-grade class-A hospitals in Guangzhou and some second-grade class-A hospitals in Foshan） knowledge for rational drug use in the elderly， and the data was statistically analyzed. RESULTS： Totally 190 questionnaires were sent out， and 176 were recycled with effective recovery of 92.63％. In the investigation， 30.11％ of the pharmacists knew the knowledge well， 23.30％ was poor， and the rest was moderate. From 20 questions， the correct answer rate more than 80％ was only 5. Pharmacists in clinical pharmacy department showed higher score than those in non-clinical pharmacy department， the difference was statistically significant （P＜0.05）； the pharmacists worked in clinical pharmacy， or pharmacists with higher title and longer working time acquired higher score， there was significant difference in the scores of pharmacists with different titles and working time（P＜0.05）； there was no significant difference among pharmacists from different grades of hospitals and education background（P＞0.05）. CONCLUSIONS： The pharmacists are not familiar with the rational use of drugs knowledge in the elderly well， and the understanding is related to working department， professional title and working time. It is necessary to strengthen the training and examination of pharmacists in rational drug use in the elderly， value and develop the construction of clinical pharmacy for the elderly actively.