The Ethnography of Ecuador consists of a diverse collection of ethnic groups, almost all related to another group in one way or another. The great majority of Ecuadorans trace their origins to one or more of three geographical sources of Human migrations: the pre-Hispanic indigenous Amerindians who settled the region over 15,000 years ago, the Europeans (principally Spaniards) who arrived over 5 centuries ago, and ultimately the black sub-Saharan Africans whom they imported as slave labour during the same period. The mixing of two or more of these three groups established other mixed ethnic groups.

Mestizos, the multiracial group of mixed European and Amerindian ancestry, are by far the largest of all the ethnic groups, and comprise around 65 per cent of the current population. The second most numerous group are the indigenous Amerindians (in Spanish indígenas, amerindios, or more controversially, indios), who account for approximately 25% of the population. Whites (in Spanish blancos) are estimated at 7%, and consists largely of those of unmixed or predominant European descent. Most White Ecuadorans are of colonial era Spanish origin, also known as criollos (literally meaning "local[-born Spaniards]", as opposed to "Peninsulares", which were Spaniards born in the Iberian Peninsula in Spain). Criollos is one of many terms from the colonial era caste system. White Ecuadorans of European non-colonial non-Spanish origin are a minority within the White Ecuadoran group, and are simply termed white. They mainly include descendants of immigrants from Italy, Germany, and France, as well as other countries. Afro-Ecuadorans make up most of the balance of the percentage, and include mulattos (mixed European and sub-Saharan African) and zambos (mixed Amerindian and sub-Saharan African).