This paper proposes a control architecture of a delivery robot system for supporting nursing staffs. There are needs of delivery in the hospital such as the medical kit delivering and the information delivering. Although these tasks are simple, the movement for the delivery spends much time. By reducing the movement time, we could reduce the load of the nursing staffs and they could focus on the caring tasks for the patients. These delivering tasks have a time constraint. This paper proposes a concept of delivery robot system for supporting the nursing staff and its control architecture for realizing the delivering tasks with a time constraint. The delivering tasks of the robot is realized based on a communication between the robot and the human. The proposed control architecture is implemented in the simulator using Robot Operating System (ROS) and the simulation result illustrates the validity of the proposed control architecture.