This study developed an innovative two-step method to synthesize hybrid gold decorated nanosheet-assembled V2O5 microflowers (Au/V2O5), through in-situ reduction of Au nanoparticles on nanosheet-assembled V2O3 microflowers at room temperature in aqueous solution and further thermal oxidization as V2O5 . Various characterization techniques were employed, such as SEM, TEM, XRD, EDX, XPS, and BET, to reveal that Au nanoparticles (diameter of similar to 10 nm) evenly attached on the surface of nanosheet-assembled V2O5 nanoparticles (diameters of similar to 1-2 mu m). This method shows several advantages in generating such nanocomposites: low cost, highly efficient, room-temperature and easy operation, as well as no need for extra reducing agents and surfactants. The gas sensing properties of the Au/V2O5 composites were investigated toward toxic 1-butylamine, an important marker compound in food and medical industries, showing that the Au modification can effectively enhance the sensing performance: high response (100 ppm of 1-butylamine), high selectivity, and low working temperature (similar to 240 degrees C), compared to bare V2O5 microflowers. The effect of the molar ratio of Au to V2O5 on nanostructure and sensing property was also investigated. The findings may bring a new insight into the fabrication of noble metal(s) modified V2O5 composites with high sensing performance. (C) 2018 Elsevier By. All rights reserved.