Purpose: This study investigated the skin-whitening effects achieved through suppressing melanin synthesis using exosomes derived from Coriandrum sativum (C. sativum). Methods: We examined the characteristics of C. sativum exosomes (CSEs) using nanoparticle tracking analysis, which revealed an average size of 152.3 nm and a concentration of 3.0×1010 particles/mL. A cytotoxicity evaluation was conducted on B16F0 cells to assess cellular safety of CSEs. We investigated the skin-whitening effects of CSEs by quantifying melanin synthesis gene expression using RT-PCR. Results: CSE concentrations less than 1.5 × 108 particles/mL did not negatively affect cellular activity. Furthermore, CSE treatment significantly decreased the expression of key genes involved in melanin synthesis such as tyrosinase, TRP-1, and TRP-2 by 75.6%, 89.1%, and 88.7%, respectively. Conclusion: CSEs hold promise as functional cosmetic ingredients that promote skin whitening by inhibiting key genes involved in melanin production.