This paper proposes a new type of rough terrain vehicle with the interconnected suspension expected to be used to demoting action. This interconnected suspension was proposed and based on posture control of rough terrain vehicle. This suspension has 4 leg-cylinders interconnected and by employing 2 AC motors it can control its posture readily. This suspension makes rough terrain vehicle simple in mechanism. By using this kind of interconnected suspension, the rough terrain vehicle can control its posture smoothly when it walks on rough terrain. In order to compensate the response delay time and improve the control system, we use preview control and the effect was proved in our research. The rough terrain vehicle can control its impact load on every wheel with the interconnected suspension. This kind of suspension can distribute impact load among wheels due to interconnecting every leg-cylinder. In our research, the reduction of impact load on vehicle wheels was proved by experiments. By making good use of the advantages of the interconnected suspension, it is possible that the rough terrain vehicle is actually applied to executing some special tasks such as demining action.