A photosensitive sensor, a manufacturing method thereof and a display panel are provided. The photosensitive sensor includes a first type semiconductor layer, an intrinsic semiconductor layer disposed on a side of the first type semiconductor layer, and a second type semiconductor layer disposed on a side of the intrinsic semiconductor layer away from the first type semiconductor layer. The intrinsic semiconductor layer is provided with metal particles capable of generating a surface plasmon effect. The metal particles are dispersely distributed in the intrinsic semiconductor layer.