Clostridium is a genus of rod-shaped, usually Gram-positive bacteria, members of which are found in soil, water, and the intestinal tracts of humans and other animals. The majority of species are obligate anaerobes. As the predominant bacteria in gut, Clostridium species exert lots of benefits to body health via interacting with intestine directly or indirectly. Clostridium species are potent candidates to alleviate dysfunctions and disorders in intestine, they have been reported to attenuate inflammation and allergic diseases effectively owing to their distinctive biological activities. Their cellular components and metabolites, like butyrate, secondary bile acids and indolepropionic acid, play a probiotic role primarily through energizing intestinal epithelial cells, strengthening intestinal barrier and interacting with immune system. In view of their salutary performances, Clostridium species have a huge potential as probiotics.