Cellulosomes produced by certain anaerobic microbes are commonly assembled from multiple subunits to macromolecular machines, and are extracellular protein complexes, which could organize and coordinate a variety of enzymic components to synergistically and effectively degrade lignocelluloses. Cellulosomes are the main forces of anaerobic hydrolytic celluloses, and play a vital role in breaking and using crystalline celluloses. The highly-efficient degradation on lignocelluloses of cellulosomes come from their self-assembled complex high-level structures, and the complex structures of the different anaerobic microorganisms have the astonishing diversity. The research advances on the diversity of assembly mode, structure, and the artificial design of cellulosomes were introduced.