Abstract Oils produced from pre-fowering and fowering plants of Micromeria juliana L. were investigated by GC/MS. The oils were qualitatively similar but differed quantitatively. After the oil fractionation by LS chromatography and GC/MS analysis, 64 compounds were identifed. Important hydrocarbons were a-pinene (7.2â10.6%) with Î²-pinene (4.9â7.0%) as monoterpenes and Î²-caryophyllene (2.5â4.2%) with Î±-gurjunene (2.1â6.4%) as sesquiterpenes. The main oxygenated monoterpenes were linalool (4.7â7.6%) with its furanoid cis- and trans-oxides (3.5â4.6%) and borneol (2.2â3.5%). Other monoterpenes, sesquiterpenes as well as non-terpenoid compounds were present in smaller amount. The results of the present research reveal some differences in the oil composition of M. juliana of Greek origin.