An enhanced wavelength-converting structure is disclosed. The enhanced wavelength-converting structure includes a substrate, a wavelength-converting layer arranged next to the substrate, and a wavelength-selective reflecting layer arranged next to the wavelength-converting layer. The wavelength-converting layer converts the first light into the second light. A part of the second light radiating backward to the light source is further reflected toward the substrate by the wavelength-selective reflecting layer to form the enhanced second light by combining with another part of the second light radiating toward the substrate.