Ankylosing spondylitis (AS) is a systemic chronic inflammatory disease primarily affecting the axial skeleton. Work disability can be one of the major consequences of AS, and the knowledge about the burden of AS to the patient and society is not well-established yet. The objective of this study was to investigate work disability among patients with AS in the national service and to put forward the related factors and differences among disabled and nondisabled groups. A total of 121 male AS patients were included in the study. Patient demographics and duration of disease were noted, and employment status and disability were questioned. Measures of functionality, axial mobility, health-related quality of life, and depression were used. It was found that 38 patients (31.4%) continued their work lives with no change, 54 patients (44.6%) changed to a lighter job, and 29 patients (24%) were retired due to AS. Differences in age at onset of the disease, time since the diagnosis, C-reactive protein (CRP) levels, and hip involvement were statistically significant. The mean retirement age of the patients was 36 +/- 4.2 years. Frequency of hip involvement was higher in the work-disabled group. Spine was evidently affected more seriously, and CRP values were higher in the work-disabled group. Older age at onset, longer time since the diagnosis, longer diagnosis delay, and some physical impairments like decrease in spinal mobility and hip involvement may preclude AS patients from leading a productive work life.