Histologic observations of elastic in periosteum have never been confirmed biochemically. Elastins were isolated, quantitated and characterized from human periosteal and pericranial tissues. Periosteum contains approximately 2.1% elastin by weight and does not appear to vary between skeletally mature and immature donors. Pericranium contains approximately 2.7% elastin by weight. These elastin contents are comparable to that reported for human skin. Amino acid analyses of the elastin from periosteum and pericranium showed the characteristic, non-polar amino acid composition of elastin. Proportions of the polar amino acids were somewhat elevated compared with elastins from the ligamentum and the aorta but were similar to those isolated from cartilaginous sources. The desmosine contents of the periosteal and pericranial elastins were comparable to those of elastins from other sources.