The International Year of Quinoa (IYQ) (2013) showcased quinoa to the world and generated a rapid expansion in international demand for quinoa. It also increased the level of consumption in Peru. Peruvian ethnic identity reflects the food culture of origin. This research aims to determine the relationship between ethnic identity and other Theory of Planned Behavior factors on quinoa consumption intention and frequency of consumers in Top Lima and Modern Metropolitan Lima, Peru. A survey of 381 respondents was conducted between April and September 2017, and structural equation modeling was used to analyze the data. Contrary to expectations, intention and frequency of consumption of quinoa were negatively affected by “ethnic identity” (p < 0.05). This result is related to the promotion by the IYQ and Marca Perú (brand name Peru) and the gastronomic boom.