Chaperonin GroEL1 in Mycobacterium tuberculosis is a product of gene duplication. As a member of heat shock proteins (HSPs), it not only promotes refolding of model substrates in vitro and in vivo, but also acts as an efficient antigen and performs function in antigen presentation. Besides, it has unique structure features, which possibly provide Mycobacterium tuberculosis with a variety series of biological functions such as regulating the cytokine-dependent granulomatous response in Mycobacterium tuberculosis infection as a protein-chaperonin, and associates with nucleoids to protect DNA as DNA-chaperonin. However, GroEL1 plays different roles in other species of Mycobacteria such as Mycobacterium smegmatis. The reasons and mechanisms of these functions need futher studies to be addressed, providing more basis for the research of the evolutionary mechanism of Mycobacterium tuberculosis.