The invention discloses a preparation method of amidoxime group uranium extraction sorbent, comprising the following steps: firstly, adopting polyacrylonitrile powder as a raw material, producing uranium extraction sorbent containing amidoxime group by amidoximation; adding titanium dioxide sol which is prepared by the sol-gel method for blending to ensure that the weight percent of titanium dioxide and polyacrylonitrile is 0.4-2.0%; producing hybridized amidoxime group uranium extraction sorbent by water washing, alcohol washing and drying. The invention has the advantages that the amidoximegroup uranium extraction sorbent material which is hybridized with titanium dioxide has higher mechanical strength, higher adsorption quantity of uranium, and higher adsorption selectivity to uraniumin the presence of calcium and magnesium ions.