As we move toward the creation of a sustainable society, much attention is being placed on artificial photosynthesis that utilizes renewable energy. Among these, active research is being done on technology for producing hydrogen from water. The technology does so through the direct decomposition of water, using a semiconductor catalyst. A major issue for semiconductor catalysts is that their visible light responsive property is not compatible with high conversion efficiency. To overcome this problem, the development of a semiconductor catalyst is in progress. Cluster is developing a new technology to produce hydrogen from water vapour using plasma activated photocatalyst. Final goal (after 4-5 years, at a lab level): energy conversion efficiency (available energy/plasma energy) – 5% or more, stable operation duration – 50 hours or more, and have a potential to be a cost competitive technology compared to existing hydrogen manufacturing methods (such as reforming steam from methanol and natural gas in the future.