The invention discloses a modified titanium dioxide composite, a wood veneer, an artificial board and a preparation method of the modified titanium dioxide composite, and belongs to the technical field of artificial boards. The preparation method of the modified titanium dioxide composite comprises: adding anhydrous ethyl alcohol into butyl titanate, heating in water bath, and stirring; adding hydrogen peroxide solution, and stirring to obtain solution A3; adding anhydrous ethyl alcohol into a beaker with deionized water to obtain solution B, dropwise adding the solution B into the solution A3, stirring, adding ferric trioxide solution, stirring, and allowing standing to obtain a ferric-ion-modified nano titanium dioxide sol precursor; stirring the ferric-ion-modified nano titanium dioxidesol precursor via a magnetic stirrer, pouring into a reactor, allowing reacting at a certain temperature for 5.5-6.5 h, taking out the reacted material, carrying out suction filtration, and drying toobtain ferric-ion-modified nano titanium dioxide powder. A preparation method of the wood veneer includes: soaking a wood veneer in citric acid solution, adding sodium hypophosphite, and carrying outsuspension C impregnating and other steps. A catalytic light source herein can be utilized more efficiently.