To improve optical absorbance in the solar spectrum region as well as to reduce solar emittance in the infrared region， a new solar absorber structure based on the double W-SiO₂ cermet layers was proposed and optimized. The factors which affect the spectral selectivity of the solar absorber such as the IR reflectance property of metal， and the volume fraction of the absorption layer were investigated. A series of W-SiO₂ cermet films with different values of volume fraction were prepared onto Si and K9 glass substrates. The measured optical constants as well as those deduced from the data fitting were used to optimize performance of the selective solar absorber. Based on the optimized parameters， the solar absorber structure with the layer parameter， consisting of that W （~150 nm） / W-SiO₂ （94 nm， 0.67HVF） / W-SiO₂ （34 nm， 0.27LVF） / SiO₂ （47 nm）， was fabricated using a magnetron sputtering system at room temperature. The experimental results agree well with the simulated ones， showing an average optical absorption of 95.3% in the wavelength region of 250～1500 nm， and a low thermal emittance of about 0.124 at 600 K in the broad wavelength region of 0.25～25 μm. Due to the simple components and high efficiency， the solar selective absorber based on the structures consisting of double W-SiO₂ cermet layers shows a good potential for practical applications in the future.