An experimental study on co-gasification of coal liquefaction residue and petroleum coke in carbon dioxide was investigated by thermogravimetric analysis. The temperature of the experiment was 1173-1323 K, and the isothermal (1273 K) kinetics were compared to evaluate the effect of loading of coal liquefaction residue on the gasification reactivity of petroleum coke. The gasification reactivity, X-ray diffraction, scanning electron microscopy images, and Brunauer-Emmett-Teller specific surface area were investigated. The results confirm that the gasification reactivity of petroleum coke was improved greatly by the catalytic components in coal liquefaction residue. The catalytic effect of the catalytic components in coal liquefaction residue was influenced by the temperature and loading. Under the condition of reaction kinetic control, higher temperature promoted the catalytic effect of coal liquefaction residue, and the catalytic effect also increased with the loading.