Sclerotinia sclerotiorum is a broad host range fungal pathogen that causes major crop losses globally. S. sclerotiorum produces molecules to promote disease including effector proteins and metabolites. Some fungal pathogens also secrete small RNAs (sRNAs), which contribute to disease by silencing host immunity genes. We sought to investigate whether S. sclerotiorum delivers sRNAs into host plant cells to attenuate host immunity during infection. In infected Arabidopsis leaf tissue, we identified S. sclerotiorum sRNAs bound to the Arabidopsis RNA-induced silencing complex (RISC) component ARGONAUTE1 (AGO1). Furthermore, we showed that predicted targets of AGO1-associated fungal sRNAs are more highly upregulated in the hypomorphic ago1-27 mutant than in the wild-type accession Col-0, indicating that S. sclerotiorum sRNAs may direct AGO1 to cleave Arabidopsis mRNA targets. Further work is underway to assess specific sRNA-mRNA interactions and to determine the role of predicted host mRNA targets in S. sclerotiorum resistance.