Abstract: Light olefins, such as ethylene and propylene, are mostly used to produce plastics, fibers and other chemicals. In views of the supplement and demand contradiction of light olefins, and the utilizing problems of heavy oil in China, coke and heavy oil cogasifying process was proposed. The principle of the process was introduced in this paper. In a fixed bed reactor, coke and Shengli residue were mixed and tested. The results indicate that the contents of light olefins can be obtained in maximal value when the temperature is in 750℃~ 800℃ and the residence time is less than 0.5s. When the residue pyrolysis in the atmosphere of gasifying and pyrolysis zone with a temperature of 750℃, the contents of light olefins (C2H4+C3H6), alkanes (CH4+C2H6) and synthesis gas (H2+CO) are 20%, 28%, and 46%, respectively. The SEM images of produced coke were observed, and it shows that the produced coke can be consumed completely by blowing oxygen. The above results show that the coke and heavy oil cogasifying process to produce light olefins and synthesis gas together has no coking problem.