Laboratory in situ combustion experiments were performed to test the concept of using in situ combustion to catalytically upgrade a medium-heavy Clair crude oil (19.8 degrees API), using a low-pressure combustion cell. Tests were performed for both noncatalytic and catalytic procedures and for both dry and wet forward combustion runs. The results showed that the presence of catalyst promotes the combustion reactions and the resultant oil was upgraded by up to I I points. High oil recoveries were achieved for all runs and ranged from similar to 53 to 74% original oil-in-place. The highest oil recovery was achieved during wet noncatalytic tests, while the lowest was achieved during the dry catalytic tests.