The mixed evergreen and deciduous broad-leaved forest in karst is a non-zonal climax forest community in southwest China. This study used three structural parameters based on the relationship between adjacent trees to analyze the spatial structural characteristics of the overall, canopy, and understory and dominant species in a 25 hm² fixed monitoring plot of the mixed evergreen and deciduous broad-leaved forest, in order to reveal the spatial structural status of the forest and provide a scientific basis for karst vegetation restoration and reconstruction. The results showed that: (1) the overall distribution pattern of the plot community was slightly aggregated and close to random distribution, with highly mixed species and similar size differentiation among individuals. The upper wood layer showed random distribution, mixed intensity, and moderate subdominant, while the lower wood layer showed aggregated distribution, mixed intensity, and moderate partial dominance. (2) Most of the dominant species in the plots were in the state of mild aggregation distribution, mixed intensity, and moderate to inferior. (3) The ratio of tree size was significant negatively correlated with DBH and tree height, while the degree of mixing was significant positively correlated with DBH and tree height. With the growth and development of trees, the dominance of tree species gradually increased, and species diversity gradually increased.It was concluded that the spatial structural of the mixed evergreen and deciduous broad-leaved forest has not been completely stable, is in the middle and late succession, and has the potential to develop into a climax community.