Owing to the effect of the Coronavirus disease (COVID-19) pandemic, the use of surgical robots to reduce the risk of infection to medical staff has been gradually increasing. In surgeries involving a surgical robot, the surgeon adjusts the robot’s arms and camera by operating an input interface with their hands and/or feet. However, owing to the diverse types of input information required for surgery, the necessity to match the operation between input information and the input interface is increasing. Thus, we propose a foot interface based on three-dimension (3D)-printer technology and verify its usefulness through a demonstration. First, the current level and direction of development of foot interfaces are reviewed through a detailed assessment of the foot interfaces used in surgical robots. Then, the hardware platform for the proposed interface is designed and fabricated using a 3D printer, and the necessary electronic systems are embedded in the hardware platform. Finally, the usefulness of this interface is demonstrated. In terms of the appropriateness of expanding the input function through the foot interface, similarities and differences in some tasks are discussed by conducting an experiment in which the same task as that of the hand interface is performed using the proposed foot interface. In addition, the ability to improve the usage of the foot interface through training is discussed.