Osteocalcin is a protein that is found in teeth and bones. This protein is secreted by bone- building cells, which are called osteoblasts, and is deposited by the body inside the bone matrix. Serum Osteocalcin is the proportion of total Osteocalcin produced that is not placed inside the bone matrix. In human body, Osteocalcin is seen as a biochemical marker, or biomarker, for the process of bone formation. High levels of serum osteocalcin have been found to be thee root cause f many bone diseases. Bone turnover and osteoporosis are results of high serum osteocalcin. Osteocalcin blood test is required to measure the level of serum osteocalcin in the body.