A new type of catalyst for deep hydrodesulfurization (HDS) has been developed. This catalyst was effective for removal of refractory sulfur compounds such as 4,6-dimethyldibenzothiophene. The addition of a small amount of zeolite which had well-controlled acidity has afforded a characteristic performance to deep HDS. We think that the zeolite added accelerates the hydrogenation rate of the dibenzothiophene ring. The developed catalyst has been manufactured on an industrial scale without any problems. The catalyst was loaded on an actual HDS unit as a demonstration run. The expected performance and stability have been obtained.