Effects of postimportation treatment of benzyladenine (BA) on vase life of imported anthurium flowers was examined after receiving the flowers in Japan and placing them either individually or together in vase solution. Cut anthuriums of two cultivars imported from Hawaii via air-freight were sprayed with 200 μg·m L–1 of BA upon arrival, and vase life of the flowers were evaluated by numerating days before observing apparent discoloration at the distal end of spadix. BA treatment significantly extended the vase life (by up to 22 d) in two cultivars in most cases during summer, but the effect was inconsistent in each cultivar when the test was done in winter. The effect of BA verified in summer was either nullified or significantly diminished by placing 10 flowers together in vase solution. In these tests, bacteria were isolated more frequently from the scape segments of bunched flowers than those of individual flowers. However, vase life was not affected when the vase solutions were inoculated with Xanthomonas axonopodis pv. dieffenbachiae. These results indicate that the postimportation BA treatment is mostly effective in extending the vase life of cut anthuriums during summer, but may not be reliable during winter in temperate regions. The preliminary evidence suggests that bacterial growth in vase solution be related to the loss of the effect of BA, but the pathogen of bacterial blight growing in the vase solution or invading the xylem of the scape is not responsible for the reduced longevity of imported anthuriums.