Aiming at the deformation and mechanical properties of the inclined rotational three-dimensional seismic isolation device,the components,defomation mechanism and mechanical property design method of the device are introduced.The horizontaltranslational stifness model and the vertical load-displacement hysteretic model are established.The horizontal translational stiffness,vertical compressive sifness and horizontal torsional stifness of the device are determined.The mechanical properties of 300type three-dimensional isolation bearings under vertical loading are tested.The results of pseudo-static test show that the verticaldefomation of the three-dimensional isolation device conforms to the theoretical mechanism.And the vertical hysteretic performance and load carying capacity are stable.Comparing the theoretical calculation values of the loading/unloading vertical stifnessand equiv alent viscous damping ratio of three-dimensional isolation device with the experimental measured values,the results showthat the theoretical and experimental results are in good agreement.Based on the finite element software,the device model is estab-lished,and the numerical simulation calculation under the same case as the static testis carried out.It is in goodagreement with thetheoretical model and the staic test curve.At the same time,the translational simulation of the three inclined bearings is carriedout.The horizontal stiffness of the device is basically consistent with the theoretical value,which verifies the validity of the theoretical model.