In our study, three kinds of metal threads used for a Qing Dynasty official’s costume were detected and analyzed using some modern techniques such as microscopic observation, scanning electron microscopy-energy dispersive spectrometry and infrared spectrometry. The structural characteristics and geometric dimensions of the metal threads, the alloy of the metal foil and the proportion of each element in the back layer were obtained. The results show that 1) the metal threads in the colored weft are silver-twined threads, and the core is silk yarn; 2) the other two kinds of metal threads with different sizes used in the Buzi are gold-twined threads. For the big ones, the core is cotton thread and for the fine ones, the core is silk yarn. The back lining materials used for the three kinds of metal threads are all paper, which is made from bamboo fiber and grass fiber filtered from the mixed bamboo and grass pulp. This study provides a more comprehensive and in-depth understanding of the current state of cultural relic conservation, and provides a reference and a basis for subsequent custody, protection and restoration work. It also presents scientific information for the study of gold application technology for textiles in the Qing Dynasty.