A robot system is provided, which includes a robot body including, robot arm and an end effector attached to robot arm, and operating device, having operating part and configured to output, when operating part is operated, operational information according to operation, a motion controller configured to control operation of robot body according to the operational information outputted from the operating device, a velocity detector configured to detect a velocity at a tip end of the end effector, a virtual reaction-force information generating module configured to output force information containing a first force component having a positive correlation to the velocity at the tip end of the end effector, as virtual reaction-force information, and a force applying device configured to give a force to the operating part in order to make an operator perceive a force according to the virtual reaction-force information outputted from the virtual reaction-force information generating module.