Abstract: This paper summarizes the microbial species anaerobically producing hydrogen, the pathways of hydrogen production and their mechanisms. It highlights on the newly developed science and technology of using cellulose and high starch content agricultural and food wastes, such as crop stalks and fruit pomace, as matrix material to produce hydrogen. By comparing among physical, chemical and biological ways of utilizing these wastes to produce hydrogen, anaerobic fermentation is concluded a very useful and efficient way for this goal. Recent studies have shown that the dark and light fermentation is a promising technique in bio-hydrogen production technique.