The 38-year-old former investment banker, who replaced left-winger Arnaud Montebourg as economy minister, declared that the "transformation of our country is not a fight against anyone" and appealed to "all those who want reconciliation and progress" to support him.
"Our political system is blocked," he said, adding that he had "seen the vacuity of our political system from the inside" and "seen how much it costs to oppose the obsolete rules of a clannish system that has become to principal obstacle to our country's progress".
Macron, who has never held elected office, created his own party, En Marche (On the Move), after resigning from the government and is to stand as its candidate rather than take part in primaries organised by the ruling Socialist Party.
He claims to be going beyond traditional left-right divisions.
En Marche now has 96,000 members and has received 2.7 million euros in donations.
Pro-business and labour law reform
While a minister, Macron pushed pro-business policies arguing they would create jobs and he is a vocal advocate of labour law reform.
The announcement had been announced in advance by his supporters and politicians of left and right have already commented on it.
The favourite to be the mainstream right's candidate in 2017, Alain Juppé, described it as "mainly a problem for the left", while Socialist Senator Luc Carvounas predicted that it would harm Juppé.
Hollande calls for unity
Asked to comment on the candidacy ahead of Macron's announcement, President François Hollande, who says he will make clear his own intentions in December, called for unity and cohesion.
"What matters is not me, it's the country," he said.
"I believe that the French people won't put their destiny in the hands of someone with no experience," former prime minister and rival to Juppé for the right nomination, François Fillon, said Wednesday morning.
Montebourg dismissed Macron as the "media's candidate who has been on 75 magazine front pages despite never having proposed anything".