A photosensitive device and a display panel are provided. The photosensitive device includes a substrate and a photosensitive functional layer. The photosensitive functional layer includes a thin film transistor layer and a quantum dot layer. The quantum dot layer is configured to emit an excitation light under an excitation of an external light. A photo-generated current efficiency of the photosensitive device can be improved, and stability and versatility of the photosensitive device can also be improved.