The bean bug, Riptortus pedestris, is one of the important pest of soybean, apple, and sweet persimmon. Since its aggregation pheromone was identified, monitoring and controlling the pest by using aggregation pheromone have been developed. Aggregation pheromone of R. pedestris is comprised of (E)-2-hexenyl (E)-2- hexenoate (E2HE2H), (E)-2-hexenyl (Z)-3-hexenoate (E2HZ3H), tetradecyl isobutyrate, and octadecyl isobutyrate. For developing more facile synthetic method, Steglich esterification was applied for syntheisis of E2HE2H and E2HZ3H under various conditions. E2HE2H and E2HZ3H were prepared in a single step with (E)-2-hexenoic acid for E2HE2H and (Z)-3-hexenoic acid for E2HZ3H, and (E)-2-hexenol in aprotic solvents (CH2Cl2, diethyl ether and toluene). Yields of E2HE2H was 59.7-77.3%, 56.1-57.7% and 75.6-77.6% under CH2Cl2, diethyl ether and toluene solvent systems, respectively (purity: 92.8-97.0%). Yield of E2HZ3H was 87.2-90.8% under CH2Cl2 condition (purity: 96.2-97.0%). The applied Steglich esterification method gave as same yield as previously reported method and saved time and cost.