Objective This study aimed to explore the effects of aerobic exercise on cognitive function in aging mice and to elucidate the underlying molecular mechanisms by which aerobic exercise ameliorates cognitive decline through the regulation of gut microbiota-metabolite network. By providing novel insights into the interplay between exercise, gut microbiota, and cognitive health, this research seeks to offer a robust theoretical foundation for developing anti-aging strategies and personalized exercise interventions targeting aging-related cognitive dysfunction.Methods Using naturally aged C57BL/6 mice as the experimental model, this study employed a multi-omics approach combining 16S rRNA sequencing and wide-targeted metabolomics analysis. A total of 18 mice were divided into 3 groups: young control (YC, 4-month-old), old control (OC, 21-month-old), and old+exercise (OE, 21-month-old with 12 weeks of moderate-intensity treadmill training) groups. Behavioral assessments, including the Morris water maze (MWM) test, were conducted to evaluate cognitive function. Histopathological examinations of brain tissue sections provided morphological evidence of neuronal changes. Fecal samples were collected for gut microbiota and metabolite profiling via 16S rRNA sequencing and ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS). Data were analyzed using a combination of statistical and bioinformatics tools to identify differentially abundant microbial taxa and metabolites and to construct interaction networks between them.Results Behavioral tests revealed that 12 weeks of aerobic exercise significantly improved spatial learning and memory capacity of aged mice, as evidenced by reduced escape latency and increased target area exploration and platform crossings in the MWM. Histopathological analysis demonstrated that exercise mitigated aging-related neuronal damage in the hippocampus, enhancing neuronal density and morphology. 16S rRNA sequencing indicated that exercise increased gut microbiota α-diversity and enriched beneficial bacterial genera, including Bifidobacterium, Parabacteroides, and Rikenella. Metabolomics analysis identified 32 differentially regulated metabolites between OC and OE groups, with 94 up-regulated and 30 down-regulated in the OE group when compared with OC group. These metabolites were primarily involved in energy metabolism reprogramming (e.g., L-homocitrulline), antioxidant defense (e.g., L-carnosine), neuroprotection (e.g., lithocholic acid), and DNA repair (e.g., ADP-ribose). Network analysis further revealed strong positive correlations between specific bacteria and metabolites, such as Parabacteroides with ADP-ribose and Bifidobacterium with lithocholic acid, suggesting potential neuroprotective pathways mediated by the gut microbiota-metabolite axis.Conclusion This study provides comprehensive evidence that aerobic exercise elicits cognitive benefits in aging mice by modulating the gut microbiota-metabolite network. These findings highlight three key mechanisms: (1) the proliferation of beneficial gut bacteria enhances metabolic reprogramming to boost DNA repair pathways; (2) elevated neuroinflammation-inhibiting factors reduce neurodegenerative changes; and (3) enhanced antioxidant defenses maintain neuronal homeostasis. These results underscore the critical role of the "microbiota-metabolite-brain" axis in mediating the cognitive benefits of aerobic exercise. This study not only advances our understanding of the gut-brain axis in aging but also offers a scientific basis for developing personalized exercise and probiotic-based interventions targeting aging-related cognitive decline. Future research should further validate these mechanisms in non-human primates and human clinical trials to establish the translational potential of exercise-induced gut microbiota-metabolite modulation for combating neurodegenerative diseases.