In this project, H-ZSM-5 catalyst was used for conversion of mixture of ethyl acetate/methyl acetate (50:50 v/v) and mixture of methanol/ethyl acetate/methyl acetate/mesityl oxide (70: 10: 10:10 v/v) to high octane number gasoline in 250, 300, 360 and 390°C and space velocity of 3.5 and 5h -1 . The major products in these reactions were aromatics with high research octane number (RON: 100-180) which detected by GC-MS. According to the results obtained in this study, in reactions of mixture of ethyl acetate/methyl acetate (50:50 v/v) over HZSM-5(9), the Claisen condensation and free-radical reactions are proposed mechanism. Also at 250°C the products formed by kinetic pathways and at higher temperatures formed through thermodynamic pathways (mostly xylenes, trimethyl benzene and other poly alkyl derivative). The reactions of the mixture of methanol/ethyl acetate/methyl acetate/mesityl oxide (70: 10: 10:10 v/v) over H-ZSM-5(9) increased the selectivity of poly alkyl benzenes (by factor of 4 to 5 times) relative to the pure methanol reaction over H-ZSM-5(9).The mesityl oxide over this catalyst produced similar distribution of alkyl aromatics, it was assumed that mesityl oxide is one of the intermediates for the aromatics.