A raindrop sensor device, including a substrate, a raindrop sensor element, a first light emitting diode, and an active element, is provided. The raindrop sensor element is located on the substrate and includes a first electrode and a second electrode separated from each other. The first light emitting diode is located on the substrate and is electrically connected to the first electrode. The first electrode and the second electrode are closer to the substrate than the active element. The active element is located on the substrate and is electrically connected to the first light emitting diode.