Objective:To explore the correlation between the expression of annexin A5(ANXA5)and ferroptosis in melanoma. Methods:The expression of ANXA5 in melanoma was analyzed using The Human Protein Atlas data and further validated by immunohistochemistry on a human melanoma tissue microarray. The B16F10 melanoma cell line was used as the research model, where ANXA5 knockout cell lines were generated using CRISPR -Cas9 technology. The effect of ANXA5 knockout on ferroptosis in B16F10 cells was assessed using CCK - 8 and lactate dehydrogenase(LDH)assays. RNA - seq was further performed to identify the possible target molecules of ANXA5 related to ferroptosis,followed by validation. Additionally,the endogenous expression of ANXA5 in different melanoma cell lines was measured to confirm its regulatory role in ferroptosis sensitivity. Results:ANXA5 was aberrantly overexpressed in melanoma tissues,and knockingdown or knockingout ANXA5 promoted the sensitivity to ferroptosis in melanoma cells. Acyl - CoA synthetase long - chain family member 4(ACSL4)as a key regulator of ferroptosis,was negatively correlated with ANXA5 expression. Overexpression of ANXA5 reduced the level of ACSL4 and showed resistance to ferroptosis. Conclusion:In melanoma cells,downregulation of ANXA5 enhanced the sensitivity to ferroptosis via upregulating ACSL4,suggesting that ANXA5 may be a potential target of ferroptosis-based therapy in melanoma.