A large literature describes the use of robots’ physical bodies to support communication with people. Touch is a natural channel for physical interaction, yet it is not understood how principles of interpersonal touch might carry over to human-robot interaction. Ten students participated in an interactive anatomy lesson with a small, humanoid robot. Participants either touched or pointed to an anatomical region of the robot in each of 26 trials while their skin conductance response was measured. Touching less accessible regions of the robot (e.g., buttocks and genitals) was more physiologically arousing than touching more accessible regions (e.g., hands and feet). No differences in physiological arousal were found when just pointing to those same anatomical regions. Social robots can elicit tactile responses in human physiology, a result that signals the power of robots, and should caution mechanical and interaction designers about positive and negative effects of human-robot interactions.