The aim of this study was to develop environmentally-friendly wood dyestuff derived from madder root (Rubia tinctorium L.) and to determine the color stability of this colorant under UV light irradiation. The dyestuff was mixed with alum and iron for mordants. Wood specimens were prepared from Scots pine (Pinus sylvestris L.) and beech (Fagus orientalis Lipsky). Wood dyestuff was applied on all surfaces of wood specimens by dipping method. Afterwards, wood panels were exposed to lightfastness test for periods of 500, 1000, and 1500 hours. Results show that almost all Solutions of madder root, compared with control, have less color changing value. Meanwhile the highest color stabilities were obtained on the wood samples treated with madder root solutions without mordant after lightfastness test.