A photovoltaic cleaning device and a windproof device thereof are provided according to the present application. The windproof device of the photovoltaic cleaning device includes a locking bracket, a locking arm, and a drive device configured to drive the locking arm to move relative to the locking bracket. The locking arm has a locking position of extending into a restricting position of the locking bracket, and a cleaning working position of exiting the restricting position of the locking bracket. During the mounting of the photovoltaic cleaning device, one of the locking arm and the locking bracket is mounted to the cleaning module, and the other is mounted to the supporting frame of the photovoltaic module.