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Abstract Small RNAs (sRNAs) of the fungal pathogenBotrytis cinereacan enter plant cells and hijack host Argonaute protein 1 (AGO1) to silence host immunity genes. However, the mechanism by which these fungal sRNAs are secreted and enter host cells remains unclear. Here, we demonstrate thatB. cinereautilizes extracellular vesicles (EVs) to secrete Bc-sRNAs, which are then internalized by plant cells through clathrin-mediated endocytosis (CME). TheB. cinereatetraspanin protein, Punchless 1 (BcPLS1), serves as an EV biomarker and plays an essential role in fungal pathogenicity. We observe numerousArabidopsisclathrin-coated vesicles (CCVs) aroundB. cinereainfection sites and the colocalization ofB. cinereaEV marker BcPLS1 andArabidopsis CLATHRIN LIGHT CHAIN 1, one of the core components of CCV. Meanwhile, BcPLS1 and theB. cinerea-secreted sRNAs are detected in purified CCVs after infection.Arabidopsisknockout mutants and inducible dominant-negative mutants of key components of the CME pathway exhibit increased resistance toB. cinereainfection. Furthermore, Bc-sRNA loading intoArabidopsisAGO1 and host target gene suppression are attenuated in those CME mutants. Together, our results demonstrate that fungi secrete sRNAs via EVs, which then enter host plant cells mainly through CME.