Limited accessibility measurements of park green spaces (PGSs) have given an account of multiple transportations when people enjoy the services. Considering the varying types and functions of PGSs, this study proposed a multi-mode method that is based on the traditional two-step floating catchment area method and relied on PGS classification to estimate spatial disparity between the supply of PGSs services and residents' demands in accessibility. Choosing the urban center of Wuhan as the study area, comparative analysis of space and statistics were conducted in accessibility between the traditional single-mode and the multi-mode methods. After a sensitive analysis of accessibility with varying travel time thresholds, underserved areas in the urban center were identified on a community level based on the PGS groups. Results indicated that the estimated accessibility average and standard deviation values by single-mode method were slimly higher than that of the multi-mode method. The average and standard deviation values of the accessibility among five time thresholds exhibited slight difference and an increasing trend. The further examination analysis of spatial accessibility in 25-min threshold demonstrated that accessibility presented spatial polarization and that most underserved areas distributed in the eastern and southwestern of the urban center in Wuhan. The findings may provide a more realistic estimation and further the knowledge of access to green spaces to help decision makers developing equal and effective planning policies and strategies. •Spatial distribution comparisons suggested that the results of the multi-mode 2SFCA based on PGS classification method were closer to the single-mode in driving in travel time threshold 25-min.•Statistical comparisons indicated that accessibility average and standard deviation values by single-mode method were slimly higher than that of the multi-mode method and exhibited slight difference with an increasing trend among five time thresholds.•Spacial accessibility under varying time threshold consistently revealed the advantage of the urban center and the disadvantage of the southwest and northeast regions.•Further examination analysis demonstrated that spatial accessibility presented spatial polarization and that most underserved areas distributed in the eastern and southwestern of the urban center in Wuhan.