Acylation of 2-methylnaphthalene (2-MN) is a very important reaction in organic synthesis, and the effiency of the continuous reactor is more than one of the batch reactor. Considering that the Friedel-Crafts acylation is a rapid exothermic reaction, in this study, we perform the acylation of 2-MN in a stainless steel microchannel flow reactor, which is characterized by high mass and heat transfer rates. The effect of reactant ratio, mixing temperature, reaction temperature, and reaction time on product yield and selectivity were investigated. Under the optimal conditions, 2-methyl-6-propionylnaphthalene (2,6-MPN) was obtained in 85.8% yield with 87.5% selectivity. Compared with the conventional batch system, the continuous flow microchannel reactor provides a more efficient method for the synthesis of 2,6-MPN. (C) 2018 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.