[Object] To provide a wristband-type information processing device, an information processing system, an information processing method, and a program through which more casual and intimate communication can be implemented.[Solution] A wristband-type information processing device includes: a band section configured to be worn on a wrist of a user; a sensor unit configured to detect a motion of the user; a vibration signal generating unit configured to generate a first vibration signal for vibrating another associated wristband-type information processing device according to the motion detected by the sensor unit; and a communication unit configured to transmit the first vibration signal generated by the vibration signal generating unit to the other wristband-type information processing device.