In the present study, we focus on the object handover task as a major example of collaborative work between a human and a robot. To achieve a smooth handover between two different agents, their mutual communication is indispensable for understanding the other’s intentions. However, previous research has not dealt with a moment during handover in which a robot takes the object from a human grasp or in which a robot hands the object to the human. It should be noted that the performance during those phases is crucial to the success or failure of the tasks because slight changes in the kinematics of the relationship between hands or fingers and object result in significant changes in grasping status: the human may forcibly pull out the object while the robot is grasping it or drop the object. Therefore, this study aims to realize a smooth handover between a human and a robot, focusing on the moment of object handover. To this end, this paper proposes to present the stiffness of the robot hand to the human. We conducted the subject experiments to investigate the effect of this method on humans in the human-robot interaction. Experimental results show that this presentation method enables the worker to recognize the stiffness of the robot, which is difficult to recognize visually, thereby reducing the workload and allowing the worker to respond seamlessly to changes in the robot’s stiffness.