Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by the aggregation of mutant Huntingtin (mHtt). Adipose-derived stem cells (ASCs) have a potential for use in the treatment of incurable disorders, including HD. ASCs secrete various neurotrophic factors and microvesicles, and modulate hostile microenvironments affected by disease through paracrine mechanisms. Exosomes are small vesicles that transport nucleic acid and protein between cells. Here, we investigated the therapeutic role of exosomes from ASCs (ASC-exo) using in vitro HD model by examining pathological phenotypes of this model. Immunocytochemistry result showed that ASC-exo significantly decreases mHtt aggregates in R6/2 mice-derived neuronal cells. Western blot result further confirmed the reduction in mHtt aggregates level by ASC-exo treatment. ASC-exo up-regulates PGC-1, phospho-CREB and ameliorates abnormal apoptotic protein level in an in vitro HD model. In addition, MitoSOX Red, JC-1 and cell viability assay showed that ASC-exo reduces mitochondrial dysfunction and cell apoptosis of in vitro HD model. These findings suggest that ASC-exo has a therapeutic potential for treating HD by modulating representative cellular phenotypes of HD.