The discoloration ingredients of rubber wood were extracted by methanol, and then were concentrated and extracted by petroleum ether, chloroform, aether, ethyl acetate, normal butanol in ascending order of the polarity. The results showed that the red discoloration components consisted of ethyl acetate, normal butanol and water of the bigger polarity. The main components of discoloration were tannin acid, phenolic and anthraquinone. And the mechanism of rubber wood red discoloration caused by tannin acid was also studied. The extracted liquid turned red no matter adding acidic or alkaline solution, but oxidizing and reducing agents having a bleach function could be used to reduce or eliminate the solution red discoloration.