A series of systematic tests are performed to study the isolation behavior of a new rubber wire cable composite vibration isolator with an electrodynamic shaker. The influences of different isolation mass, exciting amplitude and rubber material on the transmissibility of the composite vibration isolator are analyzed, and the dynamic characteristics curves of wire-cable vibration isolat or are compared with the composite vibration isolator. Results show that with the increasing of isolation mass, exciting amplitude and rubber damping, the isolation bandwidth of the composite isolator is enlarged and the transmissibility is decreased. The comparison of the dynamic characteristics curves of wire-cable and composite isolators show that the composite vibration isolator can dissipate more vibration energy and the performance is better than the wire-cable isolator at the resonance area.