In order to explore the response of plant communities in karst mountains of Central Guizhou to park utilization, the quantitative characteristics and influencing factors of plant communities in urban mountains (Mountain Parks) with park utilization and urban mountains (Natural Mountains) without development and utilization were compared and analyzed by using the relevant theories and methods of community ecology, taking Guiyang City as the research area. The results show that:(1) the ecological environment of the mountain park is relatively stable. The integrity of plant community's vertical structure is relatively high. There's a serious fault in community structure of the natural mountain under the combined action of the harsh internal ecological environment and the interference of the external urban matrix. The quantity of trees in both types of mountains show inverted "J" distribution, but the average quantity of trees which DBH ≤ 10 cm in the mountain park is significantly higher than that of the natural mountain. Compared with the mountain park, the regeneration capacity of the understory of the natural mountain is relatively weak; the height of trees in two types mountains increase with the increase of the DBH. (2) There are 604 species of plants belonging to 155 families and 457 genera, 474 species of natural mountains belonging to 142 families and 377 genera, and 437 species of mountain parks belonging to 132 families and 349 genera were recorded in the survey. On the whole, the difference of average number of species for two types of mountains is not significant, but the number of species varies widely in different mountain samples. The number of each living specie in two types of mountains shows a trend that herbs > shrubs > trees > vines. The proportion of deciduous trees and vines and perennial plant in the two types of mountains is significantly higher than that of evergreen trees and vines and annual herbs. Shrubs are usually more likely to have a percentage of evergreen species than deciduous species. (3) Plant diversity index is low in both types of mountains and there is a significant difference, the mountain park diversity index is slightly higher than the natural mountain. Plant diversity index in both types of mountains shows that the diversity index in the area with low nuclear density (level 4-6) is higher than in the area with high nuclear density (level 2-3). The diversity index of mountain parks shows the degree of parking, which is the lowest diversity index in the case of heavy park utilization and the diversity index was the highest in moderate and mild park use. (4) The overall diversity index of natural mountain is mountainside/Piedmont > mountaintop, and the diversity index of mountain park is mountainside > Piedmont > mountaintop. Plant diversity indexes of two types of mountains have no obvious distribution rule on the slope aspect. Overall, the average degree of park utilization has little effect on the karst mountain relics plant communities in the middle city of Guizhou, and the moderate degree of park utilization has a certain promotion effect on the plant community species diversity, and the heavy degree of park utilization has obviously negative effects.