This study investigates the role of mitochondrial GPX4 acetylation in cadmium (Cd)-induced renal cell ferroptosis. Exposure to Cd disrupts the arachidonic acid (ARA) metabolic pathway in mouse kidneys, leading to increased oxidized ARA metabolites and elevated levels of 4-HNE, MDA, and ACSL4. These changes are associated with mitochondrial lipid peroxidation, membrane rupture, and reduced mitochondrial SIRT3, which in turn leads to increased mitochondrial GPX4 acetylation and reduced GPX4 protein levels. Sirt3 knockout mice showed exacerbated Cd-induced GPX4 acetylation and ferroptosis, while nicotinamide mononucleotide (NMN) pretreatment reduced Cd-induced lipid peroxidation and ferroptosis in both in vitro and in vivo models. NMN also protected against Cd-induced acute kidney injury (AKI) by restoring mitochondrial SIRT3 activity and reducing GPX4 acetylation. These findings suggest that mitochondrial GPX4 acetylation, likely caused by SIRT3 downregulation, plays a key role in Cd-induced renal cell ferroptosis. The study highlights the potential of NMN as a therapeutic strategy for preventing Cd-induced AKI by targeting mitochondrial dysfunction and ferroptosis.This study investigates the role of mitochondrial GPX4 acetylation in cadmium (Cd)-induced renal cell ferroptosis. Exposure to Cd disrupts the arachidonic acid (ARA) metabolic pathway in mouse kidneys, leading to increased oxidized ARA metabolites and elevated levels of 4-HNE, MDA, and ACSL4. These changes are associated with mitochondrial lipid peroxidation, membrane rupture, and reduced mitochondrial SIRT3, which in turn leads to increased mitochondrial GPX4 acetylation and reduced GPX4 protein levels. Sirt3 knockout mice showed exacerbated Cd-induced GPX4 acetylation and ferroptosis, while nicotinamide mononucleotide (NMN) pretreatment reduced Cd-induced lipid peroxidation and ferroptosis in both in vitro and in vivo models. NMN also protected against Cd-induced acute kidney injury (AKI) by restoring mitochondrial SIRT3 activity and reducing GPX4 acetylation. These findings suggest that mitochondrial GPX4 acetylation, likely caused by SIRT3 downregulation, plays a key role in Cd-induced renal cell ferroptosis. The study highlights the potential of NMN as a therapeutic strategy for preventing Cd-induced AKI by targeting mitochondrial dysfunction and ferroptosis.