A method that substantially improves the oxidative bleaching resistance of sulfur dyed textiles is reported. Sulfur dyes are known for their poor bleaching resistance due to the sensitivity of the sulfur linkages to oxidation. This disadvantage severely prohibits the broad application of sulfur dyes because of the existence of the activated oxidative bleaching agents in many commercial detergents. In this study, 1% (w/w) of lanthanum triacetate was applied to sulfur dyed cotton fabrics via a simple padding procedure to chemically stabilize the sulfur linkages. The treatment could render sulfur dyed cotton fabrics a reduction in color changes of about 50% after laundering with detergent containing a bleaching agent, an improvement in strength retention of almost 100% after aging and an improvement in staining resistance of at least 0.5-class for about 1/3 of the sulfur dyes examined. These improvements were proved durable to repeated launderings.