Abstract: To address the applicability of vibration isolation devices under multi-dimensional and complex vibration conditions, a new three-dimensional (3D) variable damping vibration isolator upon rubber friction-extrusion mechanism is proposed, dry friction damping is applied to the three-dimensional vibration isolator, and its three-way nonlinearity is achieved through the friction-extrusion coupling mechanism. The vertical and horizontal restoring force-deformation theoretical models of the isolator are derived, and the restoring force curve is obtained through the quasi-static test. Finally, the dynamic characteristics of the isolator is studied through frequency sweep tests. The test results show that the vibration isolator has the characteristics of small damping at the equilibrium position and large damping away from the equilibrium position in all directions of vibration. The theoretical restoring force model curve is basically consistent with the test results.The model is reasonable and effective and in a certain frequency range, the vibration isolator has a good three-way vibration isolation effect. Theoretical analysis and test results can provide a reference for the research application of three-dimensional vibration isolation of equipment.