This paper introduces a novel energy-harvesting hydraulically interconnected suspension (EH-HIS) which can harvest the vibration energy traditionally dissipated into heat by the oil shock absorbers. The working modes of the EH-HIS system have been decoupled and analyzed. A mathematical model of the system was established based on the pressure drop principle and validated by the bench test. The damping characteristics and energy harvesting capability are studied by the simulations. The results show that the EH-HIS has significant asymmetric and tunable damping characteristics. When the external resistance increases from 5 Ω to 25 Ω, the corresponding equivalent damping coefficient decreases from 7558 Ns·m-1 to 3134 Ns·m-1. The analysis of energy harvesting capability shows that when the external resistance is equal to the internal resistance, the energy harvesting power achieves the maximum. And the average harvesting power can reach 875.9 W under the excitation of 2 Hz 30 mm.