The invention relates to a method for preparing polymer grade ethylene through hydrogenation for removing acetylene. A Ti-Fe-Ni hydrogenation catalyst is used, and refined ethylene materials at the tower top of an ethylene rectifying column enter an adiabatic reactor to be subjected to selective hydrogenation so as to remove micro acetylene in the adiabatic reactor, wherein the hydrogenation catalyst is a Ti-Fe-Ni catalyst, a carrier is a high-temperature resistant inorganic oxide, based on 100% by mass of the catalyst, the catalyst contains 1-8% of Fe, 0.2-1.5% of Ti and 0.5-1.8% of Ni, the specific surface area of the catalyst is 10-200m<2>/g, the pore volume is 0.2-0.63ml/g, Fe is loaded on the carrier in a macerating manner and is prepared through roasting and hydrogen atmosphere reduction, and in the catalyst, the Fe mainly exists in the alpha-Fe2O3 shape and contains FeNi phases. The catalyst is mild in reaction activity, good in operating flexibility, low in loss rate of the ethylene and even zero in the loss of the ethylene, and lower in the generation quantity of acrylic acid oligomer than that using a noble metal catalyst.