The interaction between oral microorganisms is critical for the maintenance of oral microecological balance and the occurrence of oral diseases. Studies have shown that there is a complex interkingdom interaction between the main cariogenic bacteria，Streptococcus mutans，and the main opportunistic pathogenic fungus in the mouth，Candida albicans，which may affect the clinical pathogenicity of each other. In this review，we summarized the influence of the interaction between Streptococcus mutans and Candida albicans on pathogenicity and known mechanisms. The application of natural products to control biofilms of Streptococcus mutans and Candida albicans and the virulence were also summarized.