Two ZSM-5 zeolites exhibiting micro (MZ) and nano (NZ) range crystal size have been synthesized and evaluated for their activity towards acetone to gasoline (ATG) reaction. The NZ possessed comparable acidity with that of MZ, but a significant increase in porosity (twofold increase in pore volume) was observed in case of NZ. The hierarchical pore system in NZ was observed to be responsible for enhanced catalytic activity of this material in terms of higher aromatic yields, higher octane number and increased time-on-stream stability in acetone to gasoline reaction. (C) 2012 Elsevier Ltd. All rights reserved.