True myrrh is produced by wounding the plant Commiphora myrrha (Nees) Engl. A number of oleo-gum-resins are produced from various species of Commiphora. Many of these gummy substances resemble myrrh; and sometimes are used as an adulteration of Myrrh. Generally, a complicating factor in the study and use of myrrh is the fact that most samples are obtained from the market where the plant source cannot be identified and there is often adulteration in the commercial myrrh. Myrrh oleo-gum-resin is composed of about 2-8% yellow or yellowish green, rather thick essential oil. Current study analyzed the chemical composition of six myrrh samples from Tehran and Fars (Shiraz and Larestan) in Iran as well as United Arab Emirates. The essential oil samples were yielded and subjected to Gas chromatography/ Mass spectroscopy (GC/MS) to analyze the constituents. Although there was a considerable difference in yields of essential oil extracted from studied gums, all samples represented Furanoeudesma-1, 3-diene as major constituent which was in line with previous studies. In addition, Curzerene and Lindestrene were also revealed as other main ingredients.