Given the accelerating rate of population aging and the ongoing expansion of urban areas, the mental health of the elderly within urban settings has become a matter of significant importance. Urban park green spaces, as essential elements of green infrastructure, offer not only access to natural environments and recreational opportunities but also play a vital role in facilitating psychological restoration for senior citizens. This research examines five representative urban parks in Xi’an, employing both Attention Restoration Theory(ART) and Deep Perception Theory to classify and assess plant communities according to horizontal and vertical structural dimensions. A structural equation model (SEM) was developed to investigate the relationship between the rationality of vegetation structure and the perceived psychological restoration among elderly individuals. Analysis of questionnaire data indicated a notable positive correlation between vegetation structural rationality and restorative perception. Among the four dimensions of ART, fascination exerted the most substantial influence, followed by coherence, being away, and compatibility. Significantly, the “semi-open - shrub - subtree” configuration exhibited the highest potential for restoration. These findings provide empirical evidence elucidating the internal mechanisms that link plant structural features with psychological recovery, thereby offering practical guidance for the design of age-friendly urban green spaces.