A Russian state exit poll gave him 73.9% of the vote, easily defeating his closest competitor.
The main opposition leader, Alexei Navalny, was barred from the race.
The scale of victory – which had been widely predicted – was a marked increase in his share of the vote from 2012, when he won 64% of votes.
A state exit poll put the turnout at 63.7%, down on 2012. Mr Putin’s campaign had hoped for a large turnout, to give him the strongest possible mandate.
Video recordings from polling stations showed irregularities in a number of towns and cities across Russia. Several videos showed election officials stuffing boxes with ballot papers.
Early results showed that with just 21.3% of boxes counted, Mr Putin had almost 72% of the votes.
Exit polls, published as soon as voting ended, showed that Mr Putin’s closest opponent, Pavel Grudinin, was only projected to win 11.2%.
Mr Navalny was excluded from the election because of an embezzlement conviction that he said was manufactured by the Kremlin.
Some might believe that the West’s attempts to demonize Russia, expand NATO allows Putin to appear as a populist defending Russian Sovereignty.