As a very important material, the use of hydrogen is increasingrapidly. Because the main advantage of hydrogen is that it is a clean and renewable energy source/carrier with high specific heat of combustion and no contribution to the Greenhouse effect, and can be used in many industrial applications. Many countries are developing to reduce operational cost of bio-producing hydrogen technology. So the key to realize industrialization is to improve biohydrogen-producing capacity and reduce the cost. This article discusses fermentative hydrogen production from various points of view. First, the theoretical principles of the biological processes taking place in hydrogen production, and the organisms responsible for this process are described at the same time. Second, Laboratory Experiments of fermentative hydrogen production are introduced. Types of fermentative and applicable reactor designs are discussed. Finally, the challenges faced by fermentative hydrogen production are discussed.