We have used chemical deposition of copper complex solution to prepare CuO thin films on commercial fiberglass. The deposition of copper oxides was done in a beaker using a solution of thiosulfatocuprate (I) as precursor and NaOH as a film conditioner. In order to establish a correlation between experimental conditions and the produced copper species, as well as the film quality, the as deposited and annealed samples were characterized using X-ray diffraction, visible spectrophotometry and atomic force microscopy. The most important result is that a Cu2O 80-nm film can be obtained directly with a short immersion of fiberglass into the copper solution. The film growth of this copper phase occurred in [111] and [200] directions. Moreover, this phase is converted to CuO by annealing at 375 degreesC. (C) 2004 Elsevier B.V. All rights reserved.