The mechanical behavior research on double tower connected structure under earthquake action is more and more important gradually with wide application of high-rise building connected structures in the engineering field. Structure stress and deformation become extremely complicated due to connected structure, thereby the paper adopts two kinds of different analysis software for simulation of simplified model and system comparative analysis on a project example of one double tower connected structure, single tower separate calculation and double tower connected integral calculation are respectively conducted, structure dynamic features under the earthquake action is comparatively analyzed, the influence of connected structure on tower integral structure vibration mode, displacement and period is analyzed, thereby obtaining some conclusions beneficial for project design as references.