Veneer,dyed by acid dyes,easily fades because of its poor color fastness to water.In order to improve the color fastness to water,the veneers（Betula spp.）were treated with different color fastening agents after dyeing,and the influences of the different agents to the dyed veneer were investigated in this paper.The results proved that the veneer dyed with the color fastening agent of KAl（SO4）2,compared with other five mineral salts such as Na2SO4,CuSO4,etc.,had advantages of small color variation and excellent color fastness.The veneer treated by fastening agent Y could also gain a good effectiveness but was not environmentally-friendly.The effectiveness of veneer coated by chitosan after dyeing was the best among those treated with KAl（SO4）2 and fastening agent Y,respectively,that not only had small color variation but considerably improved the stability of dyeing.