Abstract:[Objective] To examine the catalytic characteristics of gold nanoparticles (AuNPs) biosynthesized by Trichosporon montevideense WIN. [Methods] The characteristics of gold particles synthesized by incubation strain WIN with 1 mmol/L, 2 mmol/L and 4 mmol/L HAuCl4 were investigated. In addition, the AuNPs were biosynthesized by active and inactive cells of strain WIN, respectively. The morphology and particle size of the synthesized AuNPs were analyzed, and the catalytic activity of AuNPs for reduction of nitro aromatic compounds was also evaluated. [Results] When the concentration of HAuCl4 was 1 mmol/L, AuNPs were produced by strain WIN, while AuNPs and large gold particles were formed with 2 mmol/L and 4 mmol/L HAuCl4. The active and inactive cells of strain WIN could synthesize AuNPs based on the analyses of UV-vis spectroscopy and transmission electron microscopy. The synthesized AuNPs were mainly spherical, and some triangle, hexagon and parallelogram. The size of AuNPs synthesized by active cells of strain WIN ranged in 3 nm?252 nm with an average size of 45.2 nm, while the size range and average size of AuNPs synthesized by inactive cells of strain WIN were 1 nm?271 nm and 38.3 nm, respectively. The AuNPs synthesized by active and inactive cells of strain WIN could effectively catalyze the 4-nitrophenol reduction with the catalytic rate constants of 2.76×10?3 s?1 and 4.84×10?3 s?1, respectively. [Conclusion] Trichosporon montevideense WIN could be used to synthesize AuNPs and the biosynthesized AuNPs exhibited good catalytic properties, which showed a potential application in catalytic removal of the refractory pollutants in environment.