The preparation method of titanium-silicon molecular sieve (TS-1) with MFI structure is as follows: a titanium source is dissolved in ammonium tetrabutyl hydroxide (TBAOH) aqueous solution, then uniformly mixed with solid silica-gel spheres with 60-260 meshes to obtain the reaction mixture whose molar composition is SiO2:(0.0045-0.20), TiO2:(0.03-0.5), TBAOH:(0.6-40)H2O, and then the obtained reaction mixture is crystallized at 130-200 deg.C for 1-6 days in an autoclave, and processed by such processes as filtering, washing, drying and roasting according to the conventional method so as to obtain the invented product.