Nanostructured thin films on a silicon substrate were obtained by high-frequency pulse-periodic ( f ~ 8-10 kHz) action of a laser with wavelength λ = 1.064 μm and power density q = 36 MW/cm 2 on Y 0.1 Sr 0.9 CoO 3-x ceramics in a vacuum chamber at pressure p = 2•10 -2 mm Hg. Their morphology was studied using atomic force microscopy. Features of their transmission spectra in the visible and near-and mid-IR regions were revealed. The electrophysical properties of the Y 0.1 Sr 0.9 CoO 3-x structures were analyzed.