The reasonable configuration of plant community structure in landscape garden is the core factor to maintain ecological balance and landscape sustainable development. Starting from the spatial structure of plant communities, this paper proposes an evaluation index system for the spatial structure of plant communities consisting of four different dimensions, namely, horizontal structure, vertical structure, tree species composition structure and seasonal structure. The AHP-PCA entropy weight combination model was introduced as a method to assign weights to the indicator system and a test method for the indicator structure. A total of 120 landscape garden sample plots in three districts and counties of K city were selected as the research objects, and the questionnaire on the structure of landscape garden plant communities was designed by combining the natural conditions of K city with the evaluation index system of the spatial structure of plant communities. Based on the questionnaire data and AHP-PCA entropy weight combination modeling method, the evaluation index system of landscape garden plant community structure was determined. Using this index system to evaluate the plant community structure of 120 landscape garden sample plots, the highest evaluation values are between evaluation levels 1-3, indicating that the overall configuration of plant community structure in landscape gardens in K city is more reasonable.
