The Aymara ethnic group arrived in the Peruvian Altiplano in the 11th century and, after conquering the Pukinas, settled on the shores of Lake Titicaca, Peru-Bolivia. To meet its accounting and organization needs, they developed a numbering system, according to their geographical context and hand in hand with cultural syncretism, a consequence of the conquests. Within this framework, the objective of this article was to identify, analyze, and systematize the numbering system of the Aymara people. The methodology used was qualitative-ethnographic, consisting of field visits and interviews with the elderly and young people of the intervened communities, and a review of documentary sources from the colonial era (1612 and 1616), supported by the Ethnomathematics approach. The results show that there are two numbering systems, and not just one, as was previously believed, that are currently juxtaposed: the original one with a quinary base that stores quantitative and qualitative information, on which the decimal base number system was structured, eminently oral.