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.