Using Y-zeolite as starting materials of supports, new supported catalysts for copolymerization of ethylene and propylene were prepared and their possible structures were discussed. it was found the higher polymerization productivity, for instance, 10kgP/g(Ti).h can be obtained using TiCl4/Al2Et3Cl3/HY catalystic system and addition of MgClPh to this catalytic system can increase significantly the polymerization productivity.