Alonso, 32, won his 112th cap for Spain in the 2-0 defeat to Chile which confirmed their elimination from the World Cup.
With Spain's cycle of success now over, in rather brutal fashion, one of the key architects of their golden period has decided to quit, according to Marca.
Alonso won Euro 2008, the 2010 World Cup and Euro 2012 with the Spain national team and makes way for a new generation, led by the likes of Koke and Thiago Alcantara.
The Real Madrid star has been a key influence from a deep role in midfield alongside Sergio Busquets and Xavi but was not at his best in the two defeats to Netherlands and Chile which put paid to Spain's ambitions of yet another international trophy.
Marca reports his decision was taken prior to the World Cup, though.
Barcelona's Xavi could also play his final game for Spain in their dead rubber against Australia in their final group game, while uncertainty also surrounds the status of keeper Iker Casillas.
The Spanish federation has, however, backed coach Vicente Del Bosque despite Spain's struggles in Brazil.
Alonso said prior to the finals: "I haven't decided whether I will quit Spain. I'm really focused on the World Cup and it depends how I feel after the tournament. I'll decide then. If my body responds and I feel as though I want to continue, then I'll continue."