The purpose of this study was to determine the reliability and validity of the fear-avoidance beliefs questionnaire (FABQ) in assessing Korean patients with low back pain. We performed translation and cross-cultural adaptation of the questionnaire and enrolled 52 patients (18 males and 34 females) with low back pain. The subjects completed a standardized self-administered questionnaire that included the FABQ assessment along with evaluations for the visual analogue scale (VAS), Oswestry disability index (ODI), self-rating anxiety scale (SAS), and Beck depression inventory-Korean version (K-BDI). The reliability of the obtained data was determined by evaluating the internal consistency on the basis of the intraclass correlation coefficient (ICC) and the Cronbach's alpha values, while the validity of the data was examined by correlating the FABQ scores to the VAS, ODI, SAS, and K-BDI scores. The translated versions of the FABQ showed good test-retest reliability: ICC (3, 1)=.90 (FABQ for physical activity) and .97 (FABQ for work) these values were statistically significant (p<.01). The Cronbach's alpha value for FABQ was .90 (p<.01). FABQ moderately correlated with pain, disability, anxiety, and depression (p<.01). The results of this study indicate that the Korean version of the FABQ is a reliable and valid instrument for measuring fear-avoidance beliefs in Korean patients with low back pain.