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Interkingdom interactions between <i>Candida albicans</i> and <i>Staphylococcus aureus</i> promote lethal dissemination of the bacterium. During this process, <i>C. albicans</i> hypha invasion aids <i>S. aureus</i> dissemination through Als1p/Als3p-facilitated co-invasion. The effects of <i>S. aureus</i> on <i>C. albicans</i> hypha formation and invasion are, however, unknown. In this study, we used both liquid mDMEM-DMP as well as a previously constructed semi-solid adaptation of the medium (mDMEM-DMPA) to study the effects of <i>C. albicans/S. aureus</i> co-culturing on hypha formation and invasion. Semi-solid-based co-culturing significantly increased colony size and generally increased hypha invasion. Liquid growth-based time-lapse microscopy showed that <i>S. aureus</i> significantly promoted both <i>C. albicans</i> hypha length and elongation rate. Further semi-solid-based growth results revealed that >3 kDa-secreted <i>S. aureus</i> factors were accountable for the increase in <i>C. albicans</i> hypha growth. A newly constructed <i>in vitro</i> assay confirmed the co-invasion of <i>S. aureus</i> during co-culturing and showed that deletion of <i>C. albicans</i> Als1p/Als3p abolished the co-invasion of <i>S. aureus</i> during co-culturing. In conclusion, our study shows that <i>S. aureus</i> affects <i>C. albicans</i> virulence by actively stimulating <i>C. albicans</i> hypha extension through the production of, presently unknown, secreted factors and sequentially using hypha proteins Als1p and Als3p to co-invade. Therefore, <i>S. aureus</i> can stimulate <i>C. albicans</i> epithelial invasion even prior to attaching to its hyphae, providing the foundation for subsequent co-invasion.IMPORTANCEEpithelial barriers normally protect against invasion and systemic infection by <i>S. aureus</i>, but frequently, such infections occur without a port of entry. One route of <i>S. aureus</i> epithelial traversal is through co-invasion with the highly invasive <i>Candida albicans</i>. Understanding this interaction in detail is of high importance in view of the prevention of these infections. Our study shows how the <i>S. aureus</i> and C. <i>albicans</i> interaction results in mutual benefit. <i>S. aureus</i> appeared to affect <i>C. albicans</i> virulence by actively stimulating <i>C. albicans</i> hypha extension through the production of, presently unknown, secreted factors and sequentially using hypha proteins Als1p and Als3p to bind to the hyphae and co-invade. These insights are important from a microbial ecological perspective and offer important potential targets for interfering with the interaction and reducing the virulence of these opportunistic pathogens.