Abstract: The optimization of raw materials for steam cracking to ethylene with the advantage of refining-chemical integration at Zhenghai Refining & Chemical Company was introduced, focusing on expanding the raw material resources. The advantages of using light feedstock for ethylene production were discussed and feasible scheme of producing appropriate blending components for steam cracking and reforming were proposed. Since optimization, the ratio of light naphtha in ethylene feedstock reduced, gaseous feeds and high quality hydrocracked tail oil increased, thus the mass fraction of paraffin in ethylene feedstock increased 1.8 percentage points. About 15%—25% of low value products were converted to high value products in the refinery.