The aim of this study was modification ash wood (Fraxinus L.) with furfuryl alcohol and maleic anhydride as a catalyst. Investigated the effect of modifying on product color. The modification of wood was conducted out in two steps. In the first step was treatment with a mixture of modifying wood, and then curing at 105°C. the values of WPG for modifications carried out with aqueous solutions of furfuryl alcohol are lower than those carried out with furfuryl alcohol with the addition of maleic anhydride use in the furfurylation process pure solution of furfuryl alcohol did not cause large changes in color of wood ash in comparison to the control. The darkening of the wood surface was affected by the addition of maleic anhydride.