Abstract: Natural gas hydrate(NGH) is also known as combustible ice. It is widely distributed under the continental shelves, oceanic slope areas and continental permafrost horizons with immense reserves, so it is likely to be one of the most important potential energy in the future. NGH research and development has been carried out abundantly all over the world, but up to now, NGH commercial exploitation hasn't been realized yet. In this paper, patent statistics and analysis were carried out on the main technical problems involved in NGH exploitation to application by using Derwent Patent. It is indicated that the numbers of NGH patents in Japan, China and Korea are the highest, and the major petroleum and chemical industry giants in Europe and America have significant arrangement in NGH key technologies. From the viewpoint of NGH patent arrangement, China and Japan are most likely to realize the NGH commercial production, but both nations have technical weakness in patent distribution, so it is necessary to carry out research & development and patent arrangement on the weak technologies.