The invention relates to the technical field of separation membrane materials, in particular to a titanium dioxide fiber composite ceramic separation membrane and a preparation method thereof. The titanium dioxide fiber composite ceramic separation membrane is a hollow structure or hollow porous structure, and has a specific surface area of greater than or equal to 25m<2>/g. The titanium dioxide fiber composite ceramic separation membrane is obtained by: taking a ceramic membrane with a pore diameter of 100-200nm and porosity of 40%-60% as the carrier membrane, and loading polyvinyl alcohol tothe carrier membrane surface by electrostatic spinning, then impregnating the carrier membrane loaded with the polyvinyl alcohol nanofiber in a titanium alkoxide solution prepared by sol-gel method,and conducting calcination. The titanium dioxide fiber composite ceramic separation membrane obtained y the method provided by the invention has the characteristics of large specific surface area, small porosity loss, and no cause of water flux decrease, and is suitable for large-scale production and popularization and application.