Introduction and objectives Extracellular vesicles (EVs) are nanometric particles secreted from the membrane into the surrounding environment. They play a crucial role in intercellular communication through their ability to transport bioactive molecules. Various functions have been attributed to EVs produced by Staphylococcus aureus: biofilm formation, cytotoxicity, immunomodulation... These functions suggest their involvement in host-pathogen interactions and pathogenesis. However, in vivo data remain scarce to date. The aim of this work was to test the larval Galleria mellonella model to assess the impact of EVs in vivo. Materials and methods Derivated HG003 reference strain-EVs were purified by steric exclusion chromatography. Different quantities of EVs were injected into the larval circulatory system to determine the minimum lethal dose. Impact of EVs, alive bacteria and PBS buffer was compared at different times after injection, both on aspects of mortality, macroscopy/microscopy, and expression of factors of larval innate immunity (e.g., opsonins, anti-microbial peptides...) by RT-qPCR from 2 distinct environments, (i) hemolymph (HL; larval circulatory system) and (ii) fat body (FB). All experiments were performed in triplicate. Results, discussion and conclusion Preliminary data showed that only a significant quantity of EVs (1010 EVs) were responsible for early larval mortality. Microscopy data allowed us to visualize S. aureus bacteria as well as clusters of EVs, each condition exhibiting a specific immune response and cellular remodeling. The larval immune response proved to be specific to the condition tested (bacteria vs. EVs), and depended on post-infection time and localization (HL vs. FB). Compared to bacteria, EVs induced an early activation of the majority of tested-innate factors in the HL, whereas a rather late activation in the FB. In addition, certain immune players were specifically induced by EVs. The G. mellonella model therefore appears suitable for assessing the contribution of S. aureus EVs to pathogenesis.