Clarifying the impact of population aging on skill premium not only aids in formulating strategies to address the comprehensive socioeconomic challenges posed by "aging before affluence", but also helps optimize income distribution and advance common prosperity. This study employs panel data combining provincial demographic aging trends with Chinese A-share listed companies from 2012 to 2022 to estimate the extent to which population aging influences labor skill premiums in China. The results indicate that population aging will significantly increase the skill premium. This effect is more pronounced in non-state-owned enterprises, firms with high R&D intensity, high-tech industries, and manufacturing enterprises. Mechanism analysis reveals that the deepening of population aging does not drive skill-biased technological change but primarily enhances the demand for highly skilled labor through the capital-skill complementarity effect, thereby elevating the degree of labor skill premium. This suggests that current enterprises predominantly address the rising cost pressures associated with population aging though capital investment rather than technological upgrading or the research and development of new technologies. The conclusions provide theoretical and empirical foundations for policymakers to proactively address population aging, alleviate labor market pressures, and develop and refine common prosperity policies.