For application as a variable thermal emittance material in a recently-developed thermal control system for spacecraft, (La1-xSrx)MnO3-delta(LSMO) thin films with thicknesses of 1.2 mu m, 2.5 mu m, and 4.3 mu m were fabricated on yttria-stabilized zirconia (100) substrates by a pulsed laser deposition and ex-situ annealing at 1123 K in air. All the films were dense and their surface roughness was much smaller than the thermal infrared (IR) wavelength. The films had (100) and (110)-preferred orientations, and the thicker films showed more preferable growth along the (100) orientation. Temperature-magnetization curves revealed that the LSMO films exhibited a metal-insulator transition near room temperature. The thermal emittance of the films estimated from IR reflectance spectra and black body radiation spectra exhibited large non-linearity near room temperature owing to the phase transition. The change in thermal emittance of the LSMO films that were more than 2.5 mu m thick was comparable with that of the Ca-doped LSMO ceramic tiles already used as variable thermal emittance materials. Thus, this result clearly demonstrates that LSMO thin films with thickness of 2.5 mu m can work as variable thermal emittance materials in the thermal control system for spacecraft. (C) 2015 Elsevier B.V. All rights reserved.