Social judgments about other people are often made based on visual appearance. In this study, we investigatedwhether visual appearance of an interaction partner influences action coordination in social interactions. In a novel interactiveaugmented reality setup participants interacted (i.e. carried out a high-five) with a life-sized 3D avatar that was either human-looking or robot-looking. Importantly, the kinematics of the avatars were identical for both appearances. We examined whethermotion trajectories of a high-five action and other motion trajectory parameters such as velocity, radial error, synchrony, andvariability were modulated by the visual appearance of the avatar. Results showed that participants carried out the high-fivefaster and applied different motion trajectories for the human-looking than for the robot-looking avatar. These findings suggestthat visual appearance does not only influence social judgments but also the immediate behavior towards the interaction partner.