BBC News reports hackers tried to steal documents related to the G20 and international economic affairs. The attack was the first of this size and scale against the French state, it took place in December, ahead of the G20 summit in Paris in February.
No information was released about the suspected perpetrators, although an anonymous official told a French magazine that a certain amount of the information was redirected to Chinese websites.
The French finance ministry has confirmed it came under a cyber attack in December that targeted files on the G20 summit held in Paris in February.
Budget Minister Francois Baroin said an investigation had been launched, adding: "We have leads".
It follows a report in Paris Match magazine that claimed a sustained cyber attack sought documents related to the G20 and international economic affairs.
More than 150 of the ministry's 170,000 computers were affected.