This paper examines the intricate relationship between indigenous knowledge and ecological management practices of the Keiyo community of Kenya in the pre-colonial times, with a focus on how they managed their livestock economy and natural resources sustainably. While there has been some research on the Keiyo and their pastoral practices, most of the studies are often generalized or integrated into the broader Keiyo agricultural studies. Consequently, Keiyo's adaptation to their ecology in livestock production has not been sufficiently analyzed, especially in terms of how they managed their livestock economy and natural resources sustainably. This study therefore, focuses on how the Keiyo people leveraged their ecological indigenous knowledge to effectively manage and sustain their livestock economy within their unique ecological setting. This exploration emphasizes the resilience and sustainability of Keiyo’s traditional livestock practices amidst ecological challenges. Guided by Indigenous Knowledge Systems (IKS) theory, this study employed purposive and snowballing sampling techniques to select 26 key informants. Data was obtained from both primary and secondary sources, with primary data derived from field interviews and secondary data drawn from electronically stored materials on the internet, and written sources such as articles, theses, journals, books and Seminar papers. Using a historical research design, the study conducted a thematic analysis of the data. The study established that the Keiyo developed and applied sophisticated indigenous knowledge systems to manage their livestock economy and ecological resources sustainably. This finding presents valuable insight into sustainable livestock economy that could inform modern approaches to resource management, especially within the context of climate change.