A SO2 gas acceleration test was carried out on four textile groups (silk, cotton, ramie cloth, hemp cloth) which were categoried in five categories by the dyeing materials (undyed, red, yellow, blue, black) and the relation between the concentration of SO2 and deterioration rate was evaluated. The textiles were exposed to 0.01, 0.12, 1, 10, 100, 1000, and 5000 ppm of SO2 for 24 hours and the optical, physical, and chemical deterioration rates were studied. An optical change was identified as the color difference and grey scale rating (colorfastness) enhanced with the increase of gas concentration while there was little physical change. Chemical damage was caused by the acidification of the textile material due to the trapped sulfate ion concentration. The result of optical, physical, and chemical deterioration rates shows that 1 ppm/day SO2 is a critical level of deterioration of traditional textiles.