In this paper, the non-independent model is construted to study the scattering characteristic of the adjacent tree, which is particularly well adapted to the two tree trunks’ characteristic because of the complexity of the scatter. And in the dence forest, the characteristic of the adjacent trees is more important. The finite-length multi-layer dielectric cylinder was used to model the trunk,and the electromagnetic scattering model for two adjacent trunks was analyzed. This paper presented the excitation source, the ABC, the modeling and simulation’s process, then it provided the amplitude’s change according to the different distance between the two adjacent trunks and the RCS fluctuation because of the different incident angle. At last, the comparison between the two trunks and the single trunk was gived.