Objective We assessed the relationship between chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and erectile dysfunction (ED) using propensity score matching. Methods Data from 8727 middle-aged men who had undergone health checkups were analyzed. The National Institutes of Health Chronic Prostatitis Symptoms Index (NIH-CPSI), the International Index of Erectile Function-5 (IIEF), the Premature Ejaculation Diagnostic Tool (PEDT), testosterone measurement, basic blood chemistry, and metabolic syndrome (MetS) assessment were performed in this study. As in a previous study, the symptoms were classified as “no” if respondents reported no perineal or ejaculatory pain or had an NIH-CPSI pain score of <4, and the symptoms were classified as “moderate to severe” if the pain score was >7. Of the 8727 men considered, 7181 formed the cohort for propensity score matching, including 597 men with moderate to severe prostatitis-like symptoms (case) and 6584 men with no prostatitis-like symptoms (control); ultimately, however, members of the case and control groups were matched at a 1:1 ratio by propensity score. Results After matching, the variables of age, testosterone, PEDT and MetS were evenly distributed between the groups. After matching, the mean IIEF score of the case group was significantly lower than that of the control group (17.2±5.5 vs. 14.7±5.3; P<0.001). Additionally, the severity of ED was significantly greater in the case group (no, mild, mild to moderate, moderate, and severe, respectively: 27.5%, 30.2%, 24.6%, 13.1%, and 4.7% in the control group; 10.7%, 27.0%, 33.0%, 18.9%, and 10.4% in the case group; P<0.001). Finally, the rate of moderate to severe ED was significantly higher in the case group than in the control group (17.8% vs. 29.3%; P<0.001). Conclusion Moderate to severe prostatitis-like symptoms were significantly and independently correlated with ED in middle-aged men.