OBJECTIVE: To provide reference for reducing disadvantageous drug-drug interaction （DDI） and avoiding adverse drug event （ADE）. METHODS: The patients aged more than 65 were selected from cardiovascular department in our hospital during Jun. 2015-Mar. 2016. The influential factors for potential DDI（PDDI）-induced ADE were analyzed. The relationship of related factors with PDDI-induced ADE was analyzed by multivariate Logistic regression analysis. RESULTS: A total of 328 patients were included， involving 257 PDDI patients， and totally 452 cases of PDDI （including 247 cases of mild PDDI， 149 cases of general PDDI and 56 cases of severe PDDI）. The age， the number of drugs used simultaneously， Ccr and liver function （Child-Pugh score） were related to the occurrence of PDDI-induced ADE （P＜0.01）. CONCLUSIONS: For PDDI-induced ADE， the risk evaluation can be conducted for a series of factors， including age， the number of drugs used simultaneously， Ccr and liver function. For high-risk patients， intervene should be conducted in advance to reduce the risk of ADE.