Abstract: The present invention relates to a spectrally selective emitter and a design method thereof. The designed emitter has a one-dimensional layered structure, including a first layer, a second layer and a third layer arranged in sequence, wherein both the first and third layers are hafnium oxide layers, and the second layer is a hafnium oxide layer with multiple erbium oxide nanoparticles distributed. The designed emitter is a material-type emitter with spectrally selective emittance. Compared with the traditional structure-type emitter, the material-type emitter has high thermal stability and oxidation resistance, which can fundamentally solve the high-temperature degradation problem.