The choloroformic extract of Pistacia Lentiscus L. is separated and resulted in the isolation of one compound Abietadiene. The structure of the compound was detrmained by spectroscopic technique : [ IR,1H-NMR,13C-NMR, DEPT(90º) , DEPT(135º), HMQC, HETCOR, 1H-1H COSY, HMBC, Mass. ]