The invention discloses a feeding method for preparing high grade nickel matte, which comprises the following steps: a) low grade nickel matte is put into a continuous converting furnace with the temperature of 1100 DEG C to 1300 DEG C; b) slagging agent is added into the continuous converting furnace, and oxidative gas is blown into the continuous converting furnace; the oxidative gas reacts with the low grade nickel matte to produce high grade nickel matte, slag and smoke gas; the slagging agent is added into the continuous converting furnace for at least three times. Because the adding method of the slagging agent has an important influence on the reaction temperature and the reaction progress, the invention can prepare the slag separated from the high grade nickel matte through adding the slagging agent into the converting furnace for a plurality of times; meanwhile, the invention can recover the nickel in the low grade nickel matte at a higher recovery rate and reduce the nickel content in the slag.