Abstract: Gas hydrate is regarded nowadays as a new type of clean energy with large reserve and high efficiency. The estimated resource of gas hydrate, according to newest data, is twice as much as the total global fossil energy resources including oil, natural gas and coal all together. Growing demand for energy and the challenge of global warming have pushed the people to pay more attention to the huge potential of gas hydrate, which has accordingly been considered by scientists as a "strategic high for future global energy supply". In the past decade, the United States, Canada, Japan, China and other countries have launched various projects for exploration and pilot production in both the land and offshore areas successively, while India and South Korea are actively making preparation for pilot production of marine gas hydrate. This paper intends to introduce the four historical stages of world-wide exploration and research of gas hydrate, and to elaborate the distribution of global gas hydrate resources and resource potential of major countries. Based on this, the paper will focus more on recent exploration and pilot production status in both China and other countries and their future trends, with the expectation that it will benefit the natural gas hydrate exploration test and research in China.