It is well-known method to use Ethylene Oxide (ETO) as a fumigant to preserve cultural heritage from the attack of some bacteria and insects. In this article, we investigated co]or change of some cultural material upon treating ETO. The cultural material was selected from Korean paper (hanji), ancient books, blue prints, pigments (DA, DB, DC, DD, DE and DF). hemp cloths, and colored pictures (DG, DH, Dl, DJ, DK). The $Delta$E value in chromaticity coordinates for each item was obtained upon treatment with ETO at concentration of 200, 250, 380, 500, 710 g/m$^3$ respectively. The $Delta$E value was derived from the equation of L*at with the data checked 24 hr, 48 hr, and 72 hrs respectively. The Korean papers(hanji) showed slightly change in color by $Delta$E 0.8. In the case of ancient books, it showed $Delta$E 2.91 which was easily distinguishable with the naked eyes. For the almost 73％ of blue prints, the value of $Delta$E was as much as more than 4.0 that it is recommended not to use. In the case of pigments, the value of $Delta$E was ranged from 0.15 up to 4.0 so that it should be very careful before use. The hemp cloth dyed with natural indigo showed less than 1.00 in $Delta$E, while various colored hemp cloth showed wide range of $Delta$E from 1.00 to 4.00. Finally, from the fact that the color change was as small as less than 1.00 for the colored pictures, it is thought that treatment with ETO is one of method to be used to this purpose.