The invention relates to a call mechanism for providing advertisement ability to net bars, which is characterized by comprising a single chip (12), a battery (10), a voltage stabilizing circuit (11), a call key (7), a delete key (13) and a wireless emission circuit (14), wherein the single chip (12), the battery (10), the voltage stabilizing circuit (11), the call key (7), the delete key (13) and the wireless emission circuit (14) are fixed on a circuit board fixed in a shell (1), the upper shell (2) of the shell (1) is provided with a clamp position for connecting a movable board (3), the clamp position (4) connects the upper shell (2) with the movable board (3), via clamping, plugging or a connector; the button bodies of the call key (7) and the delete key (13) are arranged on the upper shell (2), and the surface of the movable board (3) is an advertisement face (23). The call mechanism can utilize net bars of dense consumption to provide advertisement and promotion, thereby effectively reducing product cost.