We described a chemical method for effectively fabricating Nb3O7(OH) nanorod and nanosheet thin films on Nb metal substrates under hydrothermal conditions. It was proposed that the nanosheets were evolved through neighboring nanorod aggregation and mergence, which was attributed to a coalescence growth mechanism. These nanostructured Nb3O7(OH) thin films could be used as catalyst for the degradation of rhodamine B aqueous solution under UV light illumination. These results suggest that our fabrication approach constitutes some promising steps for generating nanostructured films by chemical strategy, and allow us to pursue potential applications in other areas, such as sensors, catalytic oxidation, and solar cells. (C) 2012 Elsevier B. V. All rights reserved.