Paired box 6(Pax6) is one of the members of Pax polygene transcription factor family, and plays an important role in the development of pancreas, α cell differentiation, transcription and activation of glucagon gene, β cell function and expression of insulin. Pax6 is the major gene in regulating the development of β cells, and its mutation contributes to the pathogenesis of impaired glucose tolerance and early-onset diabetes mellitus. The research progress of associations of Pax6 mutation with development of pancreas and diabetes mellitus is reviewed in this paper.