Process for preparing halogen-free flame-retardant organosilane cross-linked poly-ethylene cable material

The preparation method of halogenless fire-retardant organosilane crosslinked poly-ethylene cable material is characterized by that using (by weight portion) 100 portions of low density polyethylene,5-30 portions of ethylene copolymer elastomer, 2-5 portions of silane whose general formula is RSi (OR')3 (in which R is unsaturated olefine group and R' is methyl or ethyl generally), 0.1-0.5 portion of peroxide initiator, 0.05-0.02 portion of silane hydrolysis cross-linking catalyst, 70-150 portions of fire-retardant Mg(OH)2 and 5-30 portions of fire-retardant synergist and mixing them at 160-180 deg.c and granulating so as to obtain the invented product. Said invented cable material possesses excellent fire-retardant property, high tensile strength and large extension rate at break, and its oxygen index is above 30.