This research examines the mortuary customs of the Oaxaca Barrio, one of the foreign settlements in the ancient city of Teotihuacan. The Oaxaca Barrio is associated with the Zapotec homeland in the state of Oaxaca, southern Mexico (roughly 290 miles); but many questions remain unanswered about its origins and development. The mortuary customs of the Oaxaca Barrio show how Zapotec migrants adapted to living in Teotihuacan over a considerable period of time, maintaining aspects of their homeland identity, but also generating a new cultural repertoire by which members of the enclave redefined themselves. The presence of Zapotec people in Teotihuacan has at least three distinct moments or contexts: its origins in a time of Zapotec expansion (200 B.C), the formal settlement of the Oaxaca Barrio (A.D 100), and much later in time, when the barrio shows a hybridization process with singular characteristics (A.D 300). I address in this research two important questions: Why did Zapotec migrants keep their mortuary traditions? How did migrant identity change over time? To answer these questions I present in five chapters general characteristics of the Oaxaca Barrio, theoretical concepts, and archaeological evidence that support the analysis and discussion developed about this foreign group, and finally its mortuary customs and the relationship with its ethnicity. The Zapotec migration to Teotihuacan is important because social, political, economic and ideological aspects are involved, and this topic is not only useful to archaeological studies (in one of the most important cities in Mesoamerica), also it is helpful to anthropological research about modern migrations, and studies of identity and ethnicity in the contemporary world. In Chapter I, I present a general view of the Oaxaca Barrio in Teotihuacan, the chronology and a brief review of the situation in the Zapotec area and Teotihuacan at the moment of the Oaxaca Barrio's foundation, and a general idea of the mortuary customs in each place; also in this chapter I mention the objectives of this investigation and its limits. Chapter II mentions the main theoretical concepts related with this investigation: ethnicity and hybridization, I also approach the main ideas and hypotheses about the political and social structure in the Oaxaca Barrio. Later in Chapter III, I describe the most important archaeological evidence found in each compound excavated until now in the Oaxaca Barrio, and Chapter IV shows the archaeological record of mortuary customs identified in this foreign settlement; in this section I describe four important and basic elements in the mortuary system: type of burial, offerings and practice of funerary rites, and urns. And finally in Chapter V, I present the discussion of each element, making a comparison with funerary practices and characteristics in the Zapotec area, mainly Monte Alban, and Teotihuacan culture; also in this last chapter I mention how could be the syncretism-hybridization process of this foreign settlement, mainly identified through its funerary customs.