OBJECTIVE： To investigate the influential factors of adverse drug reaction （ADR） in elderly patients during medication， and to provide reference for reducing the incidence of ADR in geriatrics department. METHODS： The clinical data of elderly patients admitted to our hospital from Jan. 2011 to Dec. 2015 were collected and analyzed by single factor and unconditional Loigstic multiple regression analysis. The risk influential factors of ADR were investigated. RESULTS： A total of 1 680 patients received drug therapy， and the incidence of ADR was 7.92％ （133/1 680）. Organs/systems involved in ADR were mainly allergic reaction （49 cases， 36.84％） and digestive system （48 cases， 36.09％）. The results of single factor analysis showed that the age of patients， drug dosage， route of administration， treatment course， the type numbers of drug combination and others were the independent influential factors of ADR. By unconditional Loigstic multiple regression analysis， it was found that the risk of ADR increased with the drug dosage， treatment course， intraverous administration and various drugs use， etc. CONCLUSIONS： It is necessary to pay attention to ADR monitoring， particularly risk factors monitoring of ADR in the elderly patients， strengthen medication guidance to improve medication compliance， take the necessary preventive measures to reduce the incidence of ADR.