A rapid shutdown device and a photovoltaic system are provided. The photovoltaic system includes an inverter and multiple serially-connected photovoltaic elements. The rapid shutdown device includes a switching circuit, a control circuit, a communication circuit and an auxiliary power circuit. The switching circuit includes a first switch and a second switch. A first terminal of the first switch is electrically connected with the positive terminal of a first photovoltaic element. A second terminal of the first switch is electrically connected with the negative terminal of a second photovoltaic element. A first terminal of the second switch is electrically connected with the negative terminal of the first photovoltaic element. The communication circuit receives a command signal from the inverter and transmits it to the control circuit. The control circuit controls the first switch and the second switch to turn on or turn off according to the command signal.