Ernesto Fonseca Carrillo, commonly referred to as Don Neto is a Mexican former drug lord, and one of the co-founders of the Guadalajara cartel; along with Miguel Ángel Félix Gallardo and Rafael Caro Quintero.
He was found guilty of taking part in the execution of DEA agent Enrique Camarena, and was sentenced to house imprisonment. He is the uncle of Amado Carrillo Fuentes, another drug smuggler and the former leader of the Juárez Cartel.