Objectives: An open study was carried out to evaluate changes in bone remodeling markers such as N-telopeptide (NTx), tartrate-resistant acid phosphatase (TRAP), total alkaline phosphatase (TAP), and bone alkaline phosphatase (BAP) during a 1-year continuous tibolone treatment in postmenopausal women. Material and methods: Thirty-six postmenopausal women were recruited for receiving tibolone 2.5 mg per day for 1 year. Densitometry and determination of biochemical markers of bone metabolism in serum and urine were performed at 1, 3, 6, and 12 months. Results: Comparing baseline with 12 month's values, BAP and all resorption markers decreased significantly. NTx began to decrease since the initiation of the treatment (baseline: 74.4±5.3; 1 month: 57.5±4.2; 12 months: 36.6±2.8). BAP increased at the first month (baseline: 37.3±2.1; 1 month: 42.6±3.0) but diminished in the following months (12 months: 23.1±1.5). TAP started to decrease significantly only after 6 months of treatment (baseline: 37.3±2.1; 12 months: 31.4±2.3) and TRAP after 3 months (baseline: 9.8±0.4; 6 months: 9.1±0.5; 12 months: 8.2±0.4). Normal bone mineral density at distal and ultradistal forearm was maintained during the 1-year treatment (baseline: 0.42±0.01; 12 months: 0.42±0.01 and baseline: 0.33±0.01; 12 months: 0.33±0.01, respectively). Conclusion: The use of tibolone 2.5 mg per day diminished progressively and significantly bone resorption and formation markers during 1-year treatment period.