Abstract: OBJECTIVE To analyze influencing factors and etiological characteristics of multidrug-resistant pathogens infection in severe pneumonia patients based on logistic regression equation. METHODS Clinical data of 480 patients with severe pneumonia admitted to the respiratory intensive care department of Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital from Jan 2020 to Dec 2022 were retrospectively collected as the research subjects, which were divided into the observation group (189 cases of multi-drug-resistant pathogens infection) and the control group (291 cases of non-multidrug-resistant pathogens infection) according to whether multi-drug-resistant pathogens infection occurred. The etiological characteristics of multidrug-resistant pathogens infection in patients with severe pneumonia and its relationship with clinical data were analyzed. The influencing factors for multidrug-resistant pathogens infection in patients with severe pneumonia were analyzed by multivariate logistic regression analysis, and the influencing factor model was built; the predictive value for multidrug-resistant pathogens infection in patients with severe pneumonia was evaluated using receiver operating characteristic (ROC) curve. RESULTS Among 480 patients with severe pneumonia, 189 cases were infected with multidrug-resistant pathogens and the infection rate was 39.38%. A total of 249 strains of pathogens were isolated, mainly gram-negative bacteria. The types of pneumonia were hospital-acquired pneumonia; pulmonary primary disease, invasive examination or treatment, combination of antibiotics, admission to the intensive care unit (ICU), and high serum C-reactive protein (CRP) level and low serum albumin level were the influencing factors for multidrug-resistant pathogens infection in the patients with severe pneumonia (P＜0.05). The influencing factor model was established as follows: Logit (P) =-10.553+ the types of pneumonia being hospital-acquired pneumonia ×1.512+ pulmonary primary disease ×1.116+ invasive examination or treatment ×0.883+ combination of antibiotics ×0.762+ ICU admission ×0.553+ high serum CRP level×0.703+ low serum albumin level×0.910. The area under ROC curve of this model for predicting multidrug-resistant pathogens infection in severe pneumonia patients was 0.914, with the sensitivity and the specificity of 85.19% and 80.41%, respectively. CONCLUSION The infection rate of multidrug-resistant bacteria is higher in patients with severe pneumonia, and gram-negative bacteria are the main pathogenic bacteria. Hospital-acquired pneumonia, pulmonary primary disease, invasive examination or treatment, antibiotic combination, ICU admission, high serum CRP level, low serum albumin level are closely related to multidrug-resistant bacteria infection in patients with severe pneumonia. The prediction model established by this method has good predictive value for multidrug-resistant bacteria infections in severe pneumonia patients.