Abstract: Interference effect is used to improve solar performance of Al-N-O selective absorbing surface. Through experiments the film structure of two Al-N-O sublayers with different thickness and metal volume fractions is established. Compared with the graded films, the bi-sublayer films have lower emittance and better thermal Stability. The new films have been used in the mass production of heat pipe evacuated tubular collectors. High solar performance (α=0.93~0.95, ε(353 K)=0.04~0.06) have been obtained on the surface of the absorber.