Mr Macron defeated far-right candidate Marine Le Pen by about 65 percent to 35 percent to become, at 39, the country's youngest president, the results showed.
He will also become the first president from outside the two traditional main parties since the modern republic's foundation in 1958.
He said a "new chapter of hope and confidence is opening".
Turnout is sharply down on the last election with just 65 percent voting, while 72 percent voted in the last election in 2012, and there are predictions the election could have the highest abstention rate in 50 years.
