Background: Although prior hospitalization has been considered as a risk factor for infection with PDR pathogens in patients with CAP, the evidence is limited, We aimed to elucidate the clinical impact of PH on these patients. Methods: This retrospective observational cohort study with prospectively collected data was conducted at Jeju National University Hospital between January 2012 and December 2014. Propensity scores were constructed, and the clinical outcomes were compared. We also conducted subgroup analyses. Results: A total of 704 patients were identified. Patients with PHAP had more comorbidities than those with CAP. The median CURB-65 and PSI scores were higher in patients with PHAP than in those with CAP. After matching according to propensity scores, the baseline characteristics of the PHAP group were similar to those of the CAP group. The isolation rate of PDR pathogens as well as the 30-day and total in-hospital mortality did not differ between the PHAP and propensity score-matched CAP patients. PHAP patients with prior antibiotic use or duration of PH ＞ 10 days showed significantly higher isolation rates of PDR pathogens. Multivariate logistic regression analysis demonstrated that prior antibiotic use was associated with the isolation rate of PDR pathogens. Conclusion: PH itself might not be related with higher isolation rates of PDR pathogens or mortality in patients with CO-pneumonia. It seems reasonable that broad spectrum antibiotic therapy for PDR pathogens should be selectively applie to PHAP patients with prior antibiotic use.