The invention discloses an irradiation resistant non-halogen low smoke flame-retardant sheathing material applied to nuclear power stations and a preparation method. The raw materials comprises ethane-vinyl acetate rubber, maleic anhydride stem grafting ethane-vinyl acetate rubber, magnesium hydroxide fire retardant, organic silicon fire retardant, nano cerium oxide, FEF, zinc stearate, stearic acid, vinyl trisilane, Aflux A-16, Aflux A-25, polycarbonate diimine(PCD-50), 2, 2, 4-trimethyl-1, 2-dihydride quinoline, antiager DDA, di-tert-butyl peroxide cumene, triene propylcyanide uric acid ester and decanedioic acid dioctyl, which are heated and mixed to obtain the materials of the invention. The invention features scientific and reasonable formula and proportion, and the process is advanced. The sheathing material features fine irradiation resistance, excellent mechanical properties and long service life, thus being a good irradiation resistant non-halogen low smoke and flame-retardant sheathing material applied to nuclear power stations.