A manual-mode operating system for a robot provided with an end-effector. The manual-mode operating system includes a display section including a screen for displaying an image of an end-effector; a first input section for an input of coordinate system data on the screen of the display section, displaying the image of the end-effector, the coordinate system data designating a manual-mode coordinate system used for describing an orientation of the end-effector; a coordinate system setting section for setting the manual-mode coordinate system at a spatial position corresponding to an input position on the screen of the display section, based on the coordinate system data input through the first input section; a second input section for an input of orientation data using the manual-mode coordinate system set through the coordinate system setting section, the orientation data instructing the orientation of the end-effector; and an orientation adjusting section for adjusting the orientation of the end-effector, based on the orientation data input through the second input section.