Background: Osteoporosis is a common disease of aging population, causing fractures and raising mortality and morbidity. Standard diagnosis usually depends on measuring bone mineral density using a dual energy X-ray absorptiometry. But it does not provide information regarding bone formation or resorption. Bone turnover markers provide information regarding bone formation or resorption before the structural changes in bone occur. The aim of the study: This study was undertaken to investigate the effectiveness of N-terminal telopeptide-1 in the diagnosis of osteopenia and osteoporosis. Materials and methods: The case-control study was conducted in 170 individuals from the Department of Orthopedic Surgery. They were divided into three groups based on bone mineral density; group I with normal BMD (n=57), group II with osteopenia (n=62) and group III with osteoporosis (n=51). Institutional ethics committee approval was obtained. Written informed consent was obtained from all the study participants. Serum N-terminal telopeptide-1 (NTX-1) was analyzed by ELISA. Statistical analysis was performed using the SPSS 16.0 version for Windows. The continuous variables were expressed as mean ± SD. ANOVA with Tukey’s HSD and ROC curve analysis were performed. Odds ratio was analyzed. Pearson correlation coefficient was obtained between BMD and NTX1. P value <.05 was considered statistically significant. Results: There was a significant increase in serum N-terminal telopeptide-1 across the groups. NTX-1 values showed correlation with BMD. The area under the curve during analysis of NTX-1 in patients with normal BMD and osteopenia and osteoporosis were 0.697 and 0.592 respectively. Conclusion: The participants were in the obese as well as over-weight category. Serum N-terminal telopeptide-1 was significantly increased across the groups indicating that bone turnover markers are associated with progression of osteoporosis