The invention provides a preparation method for a tegafur slow-release agent. The tegafur slow-release agent is prepared by selecting nanometer hollow titanium dioxide as a carrier for loading the anti-cancer drug tegafur; a PSM composite material coated with titanium dioxide is prepared according to a wet method of chemical sedimentation; nanometer hollow titanium dioxide is obtained after PSMs are removed; after being prepared according to a simple and effective impregnation method, the tegafur slow-release agent is put into a simulated body fluid, and the release rate of the tegafur slow-release agent is measured at scheduled time; the measurement results show that hollow titanium dioxide has a good effect of controlling the release of tegafur.