Abstract： Objective:To evaluate nutritional status and to analyse risk factors of acute exacerbation of chronic obstructive pulmonary disease (COPD) in the elderly.Methods:Data of elderly hospitalized patients with COPD mainly from 5 grade A, class 3 hospitals (Beijing Hospital, Shanghai Huadong Hospital, Tianjin Nankai hospital, the Second Affiliated Hospital of Medical College of Zhejiang University, Guangzhou First People′s Hospital) from January 2012 to December 2020 were retrospectively analyzed. According to the global initiative for chronic obstructive lung disease criteria (GOLD), elderly COPD patients were divided into acute exacerbation group and stable group. The differences in age, gender, medical history, anthropometry, laboratory examination, nutritional support, results of nutritional risk screening 2002 (NRS2002) and global leadership initiative on malnutrition (GLIM) were compared between the two groups after admission, and the risk factors of acute exacerbation of COPD in the elderly were analyzed by multivariate Logistic regression.Results:A total of 339 elderly patients with COPD aged 65-100 years were included in this study, including 177 cases (52.21%) in acute exacerbation stage. The detection rate of malnutrition in acute exacerbation stage was higher than that in stable stage (51.98% vs 41.98%, P<0.05). The weight, body mass index and grip strength of patients in the acute exacerbation stage were significantly lower than those in the stable period [(55.47±8.42) vs (60.63±9.30) kg, (20.52±4.25) vs (22.39±4.57) kg/m 2, (12.32±4.21) vs (16.59±2.97) kg] (all P<0.05). Spearman correlation analysis showed that the acute exacerbation of elderly patients with COPD was positively correlated with malnutrition ( r=0.443, P<0.001), and negatively correlated with body weight, body mass index and calf circumference ( r=-0.200, -0.214, -0.135, all P<0.05). Multiple Logistic regression analysis showed that acute exacerbation in elderly patients with COPD was only related to malnutrition ( OR=7.799, 95% CI: 4.466-13.622, P<0.001). Conclusions:The incidence of malnutrition in acute exacerbation stage of elderly COPD patients is high. Malnutrition is independently related to acute exacerbation of COPD.