Abstract: In this paper the authors present high precision C,O and H elemental compositions of ambers,copals,heated and pressed ambers by using Elementar vario PYRO cube elemental analyzer.The authors explore detailed organic elements of ambers and copals from different producing areas around the world,discuss elemental changes in amber maturation process,amber weathering process and amber treatment and as a result draw some valuable conclusions.(1)C,O and O elemental components of ambers,copals and treated ambers from different producing areas are different.H element of ambers and copals from different producing areas are stable,implying that the content of H element of resins did not change during the amber maturation;(2)The content of C element of Burma ambers is the highest and the content of O is the lowest.In contrast,the content of C element of copals is the low-est and the content of O element of copals is the highest.The content of C and O have reverse correlation with amber maturation;(3)Except Dominican ambers,Burmese ambers as well as Baltic ambers and copals can be separated by w(C)-w(O)diagram,which can be used to distinguish the orgins of ambers;(4)The content of O element of amber weathering skins is higher than that of inner ambers,indicating that outer crusts of ambers react with O of environment;(5)The content of C,H and O of ambers and copals do not change during heat treatment and pressed treatment.