Recently, the pine sawyer Monochamus saltuarius has been proved as a vector of pinewood nematode, Bursaphelenchus xylophilus in South Korea. This pest causes serious concern that widely distributed in the middle of South Korea and most likely to spread fast. To understand their ecological behavior, the attraction behavior of the pine sawyer was tested in the volatile samples of Pinus koraiensis by emitting different host condition. The olfactory response of the immature (0~3 days old after emergence) adults of M. saltuarius preferred the volatiles from the fresh host condition (fresh twigs, just cut twigs which wrapped with the parafilm), whereas the mature (20~30 days old) adults preferred the volatiles from the 3-day old stressed host (twigs infested by male and female, 3-day old cut twigs that were artificially damaged). In the GC and GC/MS analyses, contrary to the samples from the fresh host condition having monoterpene volatiles only, the samples from the 3-day old stressed host were revealed to have more volatiles of oxygenated monoterpenes and sesquiterpenes. The attraction assay of M. saltuarius adults to the volatile mixtures of monoterpenes, oxygenated monoterpene, and sesquiterpene appeared to be efficient when the oxygenated monoterpene mixture was necessarily treated with monoterpene mixtures.