The aim of the study was to identify factors influencing the health-related quality of life (HR-QOL) for Korean RA patients and factors associated with each dimension of the EQ-5D. Two hundred and twenty-five RA patients were recruited from one University Hospital in Seoul, South Korea. Their clinical and socio-demographic data were widely collected by means of interviews, self-administered questionnaires, and clinical examinations. Multiple logistic regression analyses were performed to determine the factors influencing QOL and factors associated with each dimension of the EQ-5D. The mean EQ-5D utility observed for Korean RA patients was 0.60 (-0.29 to 1.0). Functional disability measured with Health Assessment Questionnaire (OR = 10.0, CI 2.8-34.5), disease activity score (DAS) 28 (OR = 2.6, CI 1.4-4.9), and pain VAS (OR = 2.2, CI 1.2-4.1) was three main factors influencing on QOL of RA patients. Although the functional disability consistently showed significant associations with all dimensions, various factors were associated with the each five specific dimension of EQ-5D. Pain (OR = 2.5, CI 1.4-4.6), history of hospitalization (OR = 2.1, CI 1.0-4.3), and men (OR = 2.6, CI 1.0-6.8) were associated with lower QOL in mobility. Use of alternative medicine (OR = 2.0, CI 1.1-3.7) and disease activity (OR = 3.1, CI 1.7-5.7) were associated with lower self-care QOL. For the patients with discomfort in usual activity, pain (OR = 4.7, CI 2.4-9.2) and the presence of anemia (OR = 2.3, CI 1.2-4.5) were major influencing factors. Higher disease activity (OR = 4.5, CI 1.0-21.2) and pain (OR = 3.3, CI 1.9-5.8) were associated with the pain/discomfort dimension of EQ-5D, and the pain (OR = 3.3, CI 1.9-5.8) was an independent associating factor of anxiety/depression. The strongest determinants of lower QOL in Korean RA patients were functional disability, higher disease activity, and subjective pain. However, various factors are influencing on the QOL for RA patients according to aspects of QOL. It suggested that clinicians should pay more attention to other factors of RA patients as well as clinical remission to improve their QOL.