The volatile components from the labial glands of males of six Japanese bumblebee species were analyzed and compared. Clear species-specificity was found. Ethyl dodecanoate was identified as the major component from the glands of Bombus (Bombus) hypocrita hypocrita and Bombus (Bombus) hypocrita sapporoensis while dihydrofarnesal and dihydrofarnesol were the major components from Bombus (Bombus) ignitus. Citronellol and trans,trans-farnesol were found from Bombus (Pyrobombus) ardens ardens and Bombus (Diversobombus) diversus diversus, respectively. trans,trans-Farnesol was also found from Bombus (Diversobombus) diversus tersatus in Hokkaido. Such differences strongly suggest that these chemicals play an important role in reproductive isolation between sympatric species of Japanese bumblebees.