The Real Sociedad striker has not played for his country since the 1-1 draw with Venezuela in 2011 following a long-running disagreement with those in charge of the national side.
And ahead of the event in Brazil, which begins in June, the Mexican Football Association confirmed that Vela would not be selected in Miguel Herrera's squad.
"The player said, again, that he is not 100 per cent from a mental and emotional point of view to deal with the World Cup," the organisation said in a statement on their official website on Monday.
"In short, Carlos Vela will not be called up during this World Cup process."
Mexico will get their Group A campaign under way against Cameroon on June 13.
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