Abstract: Abstract: 【Objective】There exists a large difference in body size among individuals of the same plant species, which is an important factor for affecting the spatial structure of plant populations. In this study, we aimed to explore the types of spatial distributions of large individuals in population, examining the interaction between large and small individuals, and to provide basic information for city verdurization.【Method】Four species of dwarf bamboos were chosen from the campus of Nanjing Forestry University, namely Pleioblastus pygmaeus, Indocalamus barbatus, P. fortunei and P. argenteostriataus. We divided dwarf bamboo into two groups: large individuals(cases)and small individuals(controls), then used the second-order analysis of spatial clustering combined with the Monte-Carlo test, to analyze the spatial distribution types and calculated the intensity surfaces.【Result】The results showed that: ① The P. pygmaeus, I. barbatus and P. argenteostriataus exhibited random Poisson distribution on given distance scales and no clustering characteristics. ② The P. fortunei also exhibited a random distribution, but it is slightly weaker than the other three species; ③ The four studied dwarf bamboo species had different intensity surfaces in their corresponding study regions.【Conclusion】Difference in the body size among the dwarf bamboos can affect the dynamics of intraspecific resource(especially in space)competition. It also indicated that spatial distribution pattern of large individuals reflects the external performance of the comprehensive capacity of dwarf bamboo populations in habitats. In the natural environment, based on the individual difference in size, dwarf bamboos populations forms special spatial structures through its own regulation mechanism and a series of ecological processes.