With the accelerating aging process in China, internet dependency among older adults has garnered increasing scholarly attention, particularly given that over 110 million individuals aged 60 and above are internet users, 37% of whom spend more than five hours daily on mobile devices. This study aims to examine how role deficits—such as loss of professional value, weakened inter-generational ties, diminished social participation, and difficulties in adapting to new elderly roles—contribute to internet dependency, and further investigates whether cultural norms and social marginalization intensify this relationship. Using a mixed-methods approach incorporating qualitative surveys and quantitative regression analysis, the research reveals that role deficiencies significantly predict internet addiction through a compensatory satisfaction mechanism. Additionally, both social marginalization and prevailing cultural norms are found to reinforce this pathway. These findings underscore the interplay between structural social factors and psychological mechanisms in shaping older adults’ digital behaviors, highlighting the need for holistic interventions aimed at role reconstruction and social inclusion.