Excavated from the Western Han tomb M336 at Zhangjiashan 張家山, Hubei 湖北, and published in 2022, the *Ci Mamei 祠馬禖 bamboo manuscript has yet to receive much attention. This article serves as a preliminary study of the manuscript, providing an annotated translation of its contents, a description of its codicological features, an examination of the ritual it documents, and a survey of its linguistic characteristics. The *Ci Mamei manuscript is studied in close comparison with the Ma 馬 text from the Qin 秦 tomb M11 at Shuihudi 睡虎地, as well as bamboo strip fragments from the Han 漢 (202 bce–220 ce) Jianshui Jinguan 肩水金關 frontier that document a similar ritual. I argue that *Ci Mamei, like the Shuihudi Ma text, is a ritual manual recording instructions on the performance of a sacrificial ritual. I show that the main purpose of the *Ci Mamei and Ma rituals is to pray for the overall well-being of horses, not specifically for having more newborn foals. I then illustrate that rhyme changes in the *Ci Mamei text denote different phases of the sacrifice. Lastly, I discuss the generic and formulaic properties of the language in *Ci Mamei, noting the possibility that the manuscript was interred because its language was believed to possess apotropaic qualities.