The invention relates to a white carbon black composite powder material. The white carbon black composite powder material can be used as a good UV (ultraviolet) absorption material because of the strong absorption on UV-visible spectrum in a range of 220nm to 400nm, and also can be used as a good fluorescent or red fluorescence base stock because of the excellent optical property and the capability of emitting a very pure red fluorescence. Therefore, the white carbon black composite powder material is of special significance in the development of materials with optical functions and has potential application values in the field of photoelectrical functional materials. The preparation method of the white carbon black composite powder material comprises the following steps: oxidizing hexyl carbazole formaldehyde to prepare hexyl carbazole formic acid; and then synthesizing hexyl carbazole formic acid with activated white carbon black to obtain the white carbon black composite powder material. The preparation method is simple, is suitable for industrial production and has bright application prospects.