The 48-year-old said: “I would go to Brussels to immediately launch negotiations allowing me to give back to the French people their sovereignty.”
The right-wing leader attacked the faltering euro currency as one of the root problems of the EU and described her main economic proposals as “economic patriotism, intelligent protectionism and a return to monetary independence”.
She added: “The euro is a major obstacle to the development of our economy.”
Le Pen mooted that she was in favour of maintaining a form of common currency mechanism between France and the EU to help prevent sharp currency fluctuations.
Recent opinion polls predicted that Le Pen would finish second in April’s first round of voting – putting her through to the next round in a run-off against Les Repubicain’s François Fillon.
If pollsters are correct, France would be guaranteed a right-wing leader after five years of left-wing leadership from Francois Hollande.
Le Pen remains just ahead of centrist candidate Emmanuel Macron, who has previously claimed that Angela Merkel saved the continent’s “collective dignity” with her open-door immigration policy.