Background Hyperkyphosis cause poor posture, self-image, clinical or cosmetic deformity and well-being. Therefore, it is important to evaluate patients' perception of appearance in the rehabilitation process of individuals with hyperkyphosis. Recently Kyphosis Specific Spinal Appearance Questionnaire (KSAQ) has been developed for the assessment of appearance in hyperkyphosis patients. Objective To test validity and reliability of the Turkish version of the KSAQ. Methods Sixty-two patients with hyperkyphosis (curve above 50o), ranging in age between 12 and 22 years, was included in this study. Turkish translation/back-translation of the KSAQ was done by an expert committee. Internal consistency was analyzed using Cronbach's alpha. Validity was assessed by correlating the KSAQ with the Scoliosis Research Society-22 (SRS-22) Questionnaire. Its reliability was assessed using the test-retest method with two-week interval (Pearson's correlation coefficient) on 44 of these patients. Results Mean kyphosis angle was 60o +/- 8.9o. KSAQ total scores showed excellent internal consistency (Cronbach's alpha = 0.944) and test-retest reliability (ICC = 0.890). Moderate to strong associations were found between KSAQ total score, each item scores and self-image domain of SRS-22 (r -0.299 to -0.730, p < 0.05). KSAQ total score had moderate correlation with SRS-22 total score (r 0.423, p 0.001). Overall, the KSAQ scale showed good validity. Conclusion The Turkish version of the KSAQ is a reliable and valid patient reported outcome measure of kyphosis-specific aspects of appearance in patients with moderate hyperkyphosis.