As reported by Censor.NET citing Reuters, centrist Macron defeated Marine Le Pen, a far-right nationalist who threatened to take France out of the European Union.
His victory, which also smashed the dominance of France's mainstream parties, will bring huge relief to European allies who had feared another populist upheaval to follow Britain's vote to quit the EU and Donald Trump's election as U.S. president.
With virtually all votes counted, Macron had topped 66 percent against just under 34 percent for Le Pen.
After winning the first round two weeks ago, Macron had been accused of behaving as if he was already president. On Sunday night, with victory finally sealed, he was much more solemn.
"I know the divisions in our nation, which have led some to vote for the extremes. I respect them," Macron said in an address at his campaign headquarters, shown live on television.
"I know the anger, the anxiety, the doubts that very many of you have also expressed. It's my responsibility to hear them," he said. "I will work to recreate the link between Europe and its peoples, between Europe and citizens."
Outgoing president Francois Hollande, who brought Macron into politics, said the result "confirms that a very large majority of our fellow citizens wanted to unite around the values of the Republic and show their attachment to the European Union."
Jean-Claude Juncker, president of the European Commission, told Macron: "I am delighted that the ideas you defended of a strong and progressive Europe, which protects all its citizens, will be those that you will carry into your presidency."
Macron spoke by phone with German Chancellor Angela Merkel, with whom he hopes to revitalize the Franco-German axis at the heart of the EU, saying he planned to visit Berlin shortly.
Trump tweeted his congratulations on Macron's "big win," saying he looked forward to working with him.
Chinese President Xi Jinping said China was willing to help push Sino-French ties to a higher level, according to state news agency Xinhua.