Against the backdrop of cultural inheritance and revival in the new era, the coordinated integration of heritage parks and urban spaces has become a key issue in historical urban planning. This study takes 27 heritage parks in the central urban area of Xi’an as the research objects, constructs a spatio-temporal coupling analysis framework, comprehensively uses kernel density, standard deviation ellipse and coupling coordination model to reveal the correlation and coupling evolution characteristics of heritage parks and urban functional spaces from 2010, 2016, 2022, and analyzes the main influencing factors with the help of geographic detectors. The results show that the spatial pattern of heritage parks in the central urban area of Xi’an is "single core and four areas", and the distribution center of the functional space is inclined to the south of the city, and the coupling coordination degree gradually increases from 0.31 to 0.41. Among them, transportation convenience and population density are the main driving factors, while the intensity of cultural relics protection and hydrological characteristics have a relatively weak influence. Based on this, optimization strategies are proposed to promote the symbiotic integration of cultural heritage protection and sustainable urban development, providing scientific support for Xi’an to enhance the cultural service efficiency of heritage parks and build a "heritage park city".