The invention provides an industrial robot vision system and demonstration method thereof. The vision system includes cameras, a vision controller, an Ethernet switch, a robot controller and a robot demonstrator; the plurality of cameras are arranged in arbitrary fixed positions in a working scene or / placed at the tail end of a robot arm to move together with a mechanical arm, the vision controller and the robot controller communicate through the Ethernet switch by a gigabit Ethernet, and the robot controller is connected with the robot demonstrator. The industrial robot vision system organically integrates visual collection, labeling, training and a recognition system, the system complexity is reduced, and the reliability is improved. A visual recognition capability is added to an industrial robot conveniently through demonstration instead of programming. The method does not require a user to have professional knowledge in the field of machine vision. Applying difficulty of a machine vision product matched with the industrial robot in the fields of object recognition, quality detection, position detection, process detection and safety protection is lowered.