In order to obtain an accurate measurement of low-level aldehydes contained in diesel exhaust, aldehydes were directly collected from engine-out emission using a DNPH cartridge. Since stability of aldehyde-DNPH was changed by storage condition, suitable storage condition of the collected sample was examined. Furthermore, aldehydes concentrations during engine warm-up under low-temperature condition were obtained by analyzing the collected sample using a HPLC, and odor intensity of same exhaust was evaluated by sensory assessment. Temporal change of total aldehydes concentration was similar to that of the odor intensity.