In this contribution, we report on the optical spectra of nanocomposite based on the Al 2 O 3 nanoporous matrices with embedded ADP and KB5 nanocrystals. The reflection, absorption, and transmission spectra were recorded in the range of $\mathbf{1}-\mathbf{50}\ \boldsymbol{\mu} \mathbf{m}$. The reflection coefficient of Al 2 O 3 nanomatrices depends on the method of obtaining Al sheets, which are used for the manufacture of Al 2 O 3 host matrices. For example, the value of the reflection coefficient of nanomatrices with embedded ADP crystals was 7-5.5%, whereas this coefficient for Al 2 O 3 nanomatrices with KB5 crystals was smaller, 4.5-4.0%. The reflection spectra of the nanoporous matrices of Al 2 O 3 with the embedded ADP crystals can be decreased to $\sim \mathbf{1}\%$ in the range of $\mathbf{1}-\mathbf{10}\ \boldsymbol{\mu} \mathbf{m}$ which may be explained either as a result of high diffusion scattering or a low refractive index. In addition, the performed SEM analysis has indicated that $\mathbf{Al}_{\mathbf{2}}\mathbf{O}_{\mathbf{3}}+\mathbf{ADP}$ samples with the same pore diameter of 75 nm practically have similar percentages of the coverage area, while for $\mathbf{Al}_{\mathbf{2}}\mathbf{O}_{\mathbf{3}}+\mathbf{KB}\mathbf{5}$ samples, the coverage area is almost clean.