The coking test of blending hard coal was carried out in 2 kg cokingoven.The influence of coal modifying additive (zzz) on blend coal and coke quality was studied.The optimal size and quatity of hard coal and zzz have been chosen.The experimental results show that the optimal proposal of coal blending is of that hard coal added up to 8%(its size under 3 mm) and zzz added to 0.10%.The value of M40、M10 and CRI、CSR of coke from the optimal proposal can be up to the level of coke produced in Nanjing Iron and Steel (group) Co.,Ltd.This test also gains a good result on 40 kg testoven.