Background <p>Hearing impairment is increasingly recognized as a pivotal determinant of cognitive function. As the global population ages, the urgency to pinpoint and leverage modifiable risk factors to alleviate cognitive deterioration intensifies.</p> Objective <p>This investigation seeks to delineate the correlation between auditory deficits and cognitive capabilities, especially examining the intermediary influence of social and intellectual engagements on this dynamic.</p> Methods <p>This research utilized cross-sectional data from the 2015 iteration of the China Health and Retirement Longitudinal Study (CHARLS). A multiple linear regression model was utilized to assess the relationship between hearing loss and cognitive function. Furthermore, mediation analysis was performed to investigate the mediating role of social and intellectual activities in this association.</p> Results <p>The analysis revealed a pronounced negative association between hearing loss and cognitive function (B = -0.531, 95% CI: -0.658 to -0.390). After adjusting for social and intellectual activities, hearing loss was found to be 92.15% of the total observed effect on cognitive decline. In the mediation analysis, social and intellectual activities were found to mediate approximately 7.85% of the relationship between hearing loss and cognitive decline.</p> Conclusion <p>The findings highlight the association between hearing loss and reduced cognitive function and suggest that greater engagement in social and intellectual activities may be related to better cognitive outcomes. These results support the potential value of enhancing hearing screening and promoting activity engagement among older adults.</p>