The Cemetery of Guo State in Sanmenxia is an important archaeological site to study the culture of princes in the late Western Zhou Dynasty. In Tomb M2009, a pair of hemp shorts and a piece of hemp short gown were found. This collection of hemp fabrics is one of the few Western Zhou costumes preserved to date. The hemp fabrics are divided into two layers. The inner layer was apparently dyed with a bright red color artificially. In our study, we analyzed and identified the red particles on the hemp shorts, using energy dispersive spectrometry (EDS) and micro-confocal laser Raman spectrometry. According to the results, the main component of the red particles is ferric oxide (Fe₂O₃), which is also the main component of natural ocher, indicating that the red color on the hemp fabric was the result of dyeing with ocher. This discovery provides empirical evidence of the use of ocher for clothing dyeing in the Western Zhou Dynasty.