OBJECTIVE To evaluate the effects of pharmaceutical interventio n led by clinical pharmacists on medication appropriateness of elderly inpatients. METHODS A non-randomized concurrent controlled trial was carried out. Elderly patients admitted to two treatment groups in the geriatric department of Yancheng First People ’s Hospital since June 2021 were selected as the research objects. According to the inclusion and exclusion criteria ，the first 40 patients were selected from each of the two treatment groups （according to the order of admission time ）and set as the control group or the intervention group. The control group received routine treatment and nursing services ，and the intervention group additionally received pharmaceutical intervention led by clinical pharmacists on the basis control group. Clinical pharmacists found potential inappropriate medication （PIM）and put forward suggestions on optimization of medication regimen. American Geriatrics Society 2019 Updated AGS Beers Criteria ® for PIM Use in Older Adults （hereinafter referred to as “Beers criteria ”）and the Criteria of PIMs for Older Adults in China 2017 Edition （hereinafter referred to as “Chinese criteria ”）were used as reference tools for drug use review. The medication appropriateness index （MAI）total scores （main evaluation indicator ），the number of PIMs ，the number of drugs used ，the length of hospital stay ，the number of drug-related adverse events during hospital stay ，the number of drug regimen optimization suggestions by pharmacists ， and implementation rate of E-mail：zhihuadou@163.com optimization suggestions adopted by clinicians were compared between 2 groups at admission and at discharge. RESULTS At admission ，there were no statistically differences in MAI total scores，the number of PIMs based on Beers criteria ，the number of PIMs based on Chinese criteria or the number of drugs used between 2 groups（P＞0.05）. At discharge ，there were no statistically differences in the number of PIMs based on Chinese criteria and the length of hospital stay between 2 groups（P＞0.05），but the MAI total scores ，the number of PIMs based on Beers criteria and the number of drugs used in the intervention group were lower than those in the control group （P＜0.05）. In the intervention group，the proportion of drugs recorded as “inappropriate medication ”at admission （34.5％）was significantly higher than that at discharge（19.5％）（P＜0.05）. The difference between the number of drugs discharged from hospital and the number of drugs admitted to hospital in the control group [ 3（1-4.8)] was significantly higher than that in the intervention group [ 1（0-2.8)]（P＝ 0.012）. Compared with admission ，the proportion of drugs recorded as “inappropriate medication ”in the intervention group at discharge was significantly decreased on the basis of “effectiveness”dimension and “course”dimension （P＜0.05）. During hospitalization，clinical pharmacists put forward 70 optimization suggestions of drug regimen for the intervention group ，among which 39 suggestions were adopted and implemented by clinicians ，with an implementation rate of 55.7％. CONCLUSIONS The pharmaceutical intervention led by clinical pharmacists can improve overall appropriateness of drug use in the elderly inpatients using MAI as main evaluation indicator.