OBJECTIVES: There are approximately 2,000 hemophilia patients in Korea, but patient-reported outcome(PRO) studies involving a large number of hemophilia patients have been rarely studied. The aim of this study was to assess PROs in moderate to severe hemophilia patients in Korea. METHODS: It was a cross-sectional, multi-centered and observational study. Moderate to severe, male hemophilia patients aged 8 to 65 were recruited at 2 of Korea Hemophilia Foundations and 3 other pediatrics from November 2012 to September 2013. All patients completed self-reported questionnaires to measure patients' characteristics and PROs including health-related quality of life(HRQoL) and productivity loss. HRQoL was examined using EQ-5D, ranged 0-1, which higher values indicate better HRQoL and Heamo-QoL, ranged 0-100, where higher values imply lower HRQoL. Productivity loss was estimated with absenteeism and presentism in terms of lost productivity time(LPT). RESULTS: For a total of 605 patients(mean age, 29.3 years; 88.6% with severe hemophilia) enrolled in this study, the mean scores of heamo-QoL and EQ-5D were 32.28 and 0.68 respectively. The mean scores of EQ-5D in this study are comparable to 0.68 in rheumatoid arthritis patients from Korea Observational Study Network for Arthritis. Significantly lower EQ-5D was found in patients with the following clinical factors compared to those with reverse conditions; joint bleedings(0.68 vs. 0.73, p=.001), hemophilic joint health(0.67vs. 0.73, p<.001) or disability(0.65 vs. 0.70, p<.001) as similar as in the results of Haemo-QoL. With patients who were either on a job or students(n=467, 77.2%), LPT was estimated at 127.81 hours per month on average. Of 467, patients with inhibitor or disability showed higher LPT compared to those without inhibitor(130.61 vs. 126.61 hours per month, p=0.486) or disability. (132.27 vs. 124.95 hours per month p=.087) CONCLUSIONS: The study findings suggest that patients’ clinical characteristics should take into account for the management of hemophilia given patient-reported outcomes differed by clinical manifestations.