Abstract: The traditional air-cooled condenser structure systems made up of steel trusses and reinforced concrete columns hardly satisfy the requirements for highly seismic regions in a 1000MW unit thermal power plant, a new air-cooled condenser structure system consisting of steel slant supports, steel trusses and reinforced concrete columns is proposed and its aseismic behavior is studied by experimental tests. Selecting a 1/4 substructure, a 1/8 scale model is constructed, the dynamic properties of the model are measured, and pseudo-dynamic and pseudo-static tests are carried out to study the hysteretic behaviour, deformation performance and failure mode of the structure. The results indicate that the structure can satisfy the requirements of highly seismic regions in a 1000MW unit thermal power plant, and the displacement-load curve is plump with good energy dissipation capacity and deformation performance.