This study aims to explore gender differences in the functional development of older adults in China and the influencing factors of functional trajectories among older adults，to provide a basis for formulating gender-sensitive health intervention strategies for older adults. Using data from the China Health and Retirement Longitudinal Study（CHARLS）from 2011 to 2020，individuals aged 60 and above were selected as the study population. Group - based trajectory modeling（GBTM） was employed to identify the dynamic functional trajectories by gender，and analyze the influencing factors. Significant gender differences were found in the functional development trajectories among older adults. The trajectories of men were classified as“stable and healthy”“low baseline - stable - then declining”“low baseline - rapidly increasing”and“high baseline - slowly increasing”. Among women，the categories were“stable and healthy”“low baseline-declining-then stable”“low baseline-rapidly increasing”and“high baseline-slowly increasing”. The proportion of women in the“stable and healthy”trajectory was lower than that of men. Demographic characteristics，lifestyle，and health status significantly influenced the likelihood of individuals entering different functional trajectories，with influencing factors varying across genders. Given the evident gender - specific patterns and heterogeneity of functional development among older adults，it is essential to establish dynamic，gender-specific intervention mechanisms to advance precise and personalized health management strategies for older adults.