The purpose of this research was to analysis compounds of unpleasant odor from the cotton fabrics in dehydration and drying process during washing. The cotton fabrics were treated with various commercial detergents and fabric softener or cationic surfactants such as Cetyltrimethylammonium bromide(CTAB) and Benzalkonium chloride(BC), then dehydrated and dried. The compounds of odor impregnated in fabric were detected by using CC-MS. The results are as follows: The fabrics treated with a powder-type detergent, CTAB and BC gave out compounds unpleasant odor. n-Butyraldehyde and isobutyaldehyde produced during microorganism growth were revealed as source of the compounds of the unpleasant odor. However, no aldehydes were detected from the fabrics treated with commercial fabric softener which seems to act as a deodorizer.