Background: We evaluated the relationship between bone mineral density (BMD) and biomarkers of bone turnover in ankylosing spondylitis (AS) patients treated with anti-tumor necrosis factor alpha (TNF-α) agents. Methods: Fifty-one AS patients were screened, of which 27 were started on anti-TNF therapy in accordance to the assessment of AS guidelines. Detailed assessments of erythrocyte sedimentation ratio (ESR), Bath AS disease activity index (BASDAI), Bath AS functional index (BASFI), Bath AS metrological index (BASMI), AS disease activity score-ESR, and AS quality of life (AsQOL) questionnaire were done at baseline and 6 months. Vitamin D, parathyroid hormone, and osteocalcin were measured along with BMD of the lumbar spine, anteroposterior (AP) and lateral view, and hip. Results: Out of 27 patients, 12 patients had osteoporosis. At 6 months, significant improvements were seen for BASDAI (mean 2.33 ± 1.08, P Conclusion: Anti-TNF-α has a beneficial effect on bone metabolism resulting in improved bone formation.