The advances of research on the pathogenicity and pandemicity of Vibrio cholerae in recent years are reviewed. The gene ctxAB encoding cholera toxin CT is not a native component of Vibrio cholerae genome, while it originally comes from a bacteriophage CTXΦ. CTXΦ can specifically infect Vibrio cholerae and integrate into its genome, forming a prophage; while it can also secrete CTXΦ under the induction of the environmental factors.RS1 and CTX gene elements not only closely located in chromosome position, but also closely related functionally. RS1 element can also transform into a filamentous phage RS1Φ, secrete and transfer horizontally. VPI comes from VPIΦ,which can transmit between Vibrio cholerae strains, and it is the bridge for Vibrio cholerae to acquire CTX gene element. Two gene regions VSP-Ⅰ and VSP-Ⅱ closely related to pandemicity of the Vibrio cholerae were identified recently. The relationship between pathogenicity and pandemicity is discussed.