This study evaluates the loss of balance and fall risk in patients with Ankylosing Spondylitis (AS), and assesses their relationship with disease activity, functional status, spinal mobility, quality of life and enthesitis score. Method: Included in the study were 50 AS patients who were diagnosed in accordance with the modified New York criteria, and 50 healthy volunteers of similar age and gender. For the AS patients, disease activity was assessed using the Bath Ankylosing Spondylitis Activity Index (BASDAI) and Ankylosing Spondylitis Disease Activity Score (ASDAS) C-reactive protein/Erythrocyte sedimentation rate (CRP/ESR); functional status was assessed using the Bath Ankylosing Spondylitis Functional Index (BASFI); spinal mobility was assessed using the Bath Ankylosing Spondylitis Metrology Index (BASMI); and quality of life was assessed using the Ankylosing Spondylitis Quality of Life Questionnaire (ASQoL). Additionally, a Short form-36 (SF-36) was used to assess quality of life in both the AS patients and the healthy control group; while a Timed Up and Go-test (TUG), Functional Reach Test (FRT), Berg Balance Scale (BBS) and Tinnetti's Falls Efficacy Scale (TFES) were used to assess balance and fall risk. Enthesitis in the AS patients was evaluated using Maastricht Ankylosing Spondylitis Enthesitis Score (MASES). Results: A comparison of the AS patients and the healthy controls in terms of BBS, FRT, TUG and TFES revealed balance loss and fall risk to be higher in the AS patient group, to a statistically significant degree (p<0.001). BBS, FRT, TUG and TFES were statistically significantly correlated with BASDAI, BASMI, BASFI, ASDAS-ESR, ASDAS-CRP and ASQoL in AS patients (p<0.05), while no statistically significant