In order to protect unearthed bronze artifacts, it is necessary to remove any powdery rust found on the wares. Powdery rust is mainly composed of atacamite and paratacamite, both of which have distinctive infrared spectral characteristics, making the rust identifiable by infrared microspectroscopy. Compared with the traditional compression-type Fourier transform infrared (FTIR) spectroscopy, the transmission infrared microspectroscopy method we used is faster and a more sensitive way to analyze samples with less consumption of sample, and no requirement for tabletting. In this study, the transmission infrared microspectroscopy was used to analyze the bronze corrosion products on bronze test samples, namely bronze relics from the laboratory archaeological and conservation project for the coronet of Emperor Sui Yang’s Empress Xiao, located in Caozhuang of Yangzhou, Jiangsu Province. The results show that this method can identify powdery rust efficiently and accurately.