For a study, researchers sought to identify risk markers for multi-drug resistant bacteria (MDRB)-related ventilator-associated pneumonia (VAP) in septic shock patients who had previously carried MDRB. From 2010 to 2020, this retrospective study was carried out in a medical ICU. Patients with septic shock who were still in the ICU after 48 hours were eligible. Extended-spectrum beta-lactamase-producing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus, multi-drug resistant Pseudomonas aeruginosa, imipenem-resistant Acinetobacter baumanii, and Stenotrophomonas maltophilia were designated as MDRB. MDRB colonization screening was performed both at ICU admission and during ICU stay. A time-dependent cause-specific Cox model was used to assess the determinants of MDRB-related VAP. There were 643 patients studied, and 122 (18.9%) had at least 1 episode of VAP. Overall, 32.5% of ICU patients died. The prevalence of MDRB carriage was 31%, divided into MDRB carriage at admission (14.3%) and MDRB acquired during ICU stay (16.7%). MDRB colonization in the ICU was independently associated with an increased risk of VAP (CSH: 1.85; 95% CI: 1.05–3.23; P=0.03), whereas carriage before admission was not. Imported and acquired MDRB carriage carries different risks of subsequent MDRB-related VAP in septic shock patients.