Objective To analyze affecting factors of multidrug-resistant (MDR) bacterial infection in elderly patients with acute attack of chronic bronchitis with a view of providing reference for clinical prevention and control. Methods The clinical data were retrospectively reviewed of 313 elderly patients with acute attack of chronic bronchitis from September 2015 to May 2019. Infection rate and distribution of infectious strains were analyzed. SPSS statistics 19.0 was used for statistical analysis. Univariate and multivariate regression analysis were performed to identify independent affecting factors of MDR bacterial infections in elderly inpatients with acute attack of chronic bronchitis. Results Of 313 elderly inpatients with acute attack of chronic bronchitis, MDR bacterial infection was detected in 107(34.19%). A total of 301 pathogenic bacteria were isolated from clinical specimens, 118(39.20%) being multidrug resistant. Univariate analysis showed that age ≥70 years, history of diabetes mellitus, combined use of antibiotics ≥ 3 kinds in the past 6 months before admission, length of hospital stay ≥ 14d, pulmonary heart disease, admission to Intensive Care Unit (ICU), glycosylated blood protein >7%, types of antibiotics ≥ 3 kinds after admission, combined use of antibiotics after admission ≥ 3 kinds,fasting blood glucose ≥ 11.1mmol/L, the time of using antibiotics after admission > 7d were the risk factors of MDROs infectionin elderly patients with chronic bronchitis at acute stage (P<0.05), while oral care and aerosol inhalation were the protective factors of MDROs infection in elderly patients with chronic bronchitis at acute stage (P<0.05). Multivariate logistic regression analysis showed that the independent risk factors of MDROs infection were age>70 years, combined use of antibiotics>3 kinds within 6 months before admission, admission to ICU, glycosylated menstrual protein>7%, and combining used antibiotics>3 kinds after admission (P<0.05). Conclusion MDR bacterial infection in elderly inpatients with acute attack of chronic bronchitis is associated with many factors, and infection rate can be reduced by controlling blood sugar, reducing complications of pulmonary heart disease, paying attention to the recent use of antibiotics before admission, reducing unnecessary admission to ICU, and rational use of antibiotics.