Bipolar disorder is a severe mental disorder characterized by mood fluctuations， with cognitive impairment being one of its key clinical features that seriously affects patients' social functions. In recent years， increasing evidence has indicated that oxidative stress imbalance may serve as a crucial pathophysiological basis for cognitive dysfunction in bipolar disorder. This review summarizes current research progress on oxidative stress-related biomarkers in cognitive impairment of patients with bipolar disorder， focusing on their roles in antioxidant defense， lipid peroxidation， neurotrophic factors， mitochondrial function， and telomere damage. Existing evidence suggests that oxidative stress is closely linked to processes such as neuroplasticity and cellular aging， potentially affecting cognition through multiple interacting pathways. This review also discusses the limitations in current studies， with the aim of informing future research on mechanism integration， longitudinal validation， and standardization of cognitive assessment methods.