SummaryProcessed bamboo culms capable of maintaining the greenish color in their skin have increased economic value. The use of protectors to preserve the green color and to improve the color fastness of bamboo culms has, therefore, attracted great interest in the industry. In this paper three exposure tests, including accelerated UV lightfastness, outdoor weathering, and indoor exposure, were used to evaluate the color fastness of ma bamboo (Dendrocalamus latiflorusMunro) treated with chromium based reagents. Experimental results revealed that bamboo culms treated with CCP (chromated copper phosphate) or CP (chromated phosphate), both homemade by the authors, exhibited excellent color fastness. Among all inorganic salt-treated bamboo culms the CP-treated samples had the brighter greenish skin and also provided the best green color fastness. It was further noticed that ultraviolet light plays an important role on the color conversion of CrO3-treated bamboo. The green color becomes significantly enhanced with increased exposure time.