A medical manipulator system includes: a manipulator having a treating portion at a distal end thereof； an endoscope configured to capture an image showing a state of the treating portion performing treatment； an external-force detecting means for generating data on an external force exerted on the manipulator； a display for an operator； and a controller comprising a hardware including at least one processor. The at least one processor is configured to: receive the data from the external-force detecting means； generate an auxiliary image in which a display form thereof is changed on the basis of the data； receive the image from the endoscope； determine a display position of the auxiliary image in the image on the basis of the data； generate a signal being capable to display a composited image which is superimposed on the auxiliary image on the image on the basis of the display position； and transmit the signal to the display.
