A poll by Times Radio saw the MP for Islington North, who took the Labour Party to its worst general election loss since 1935, defeat former Liberal Democrat leader Charles Kennedy in the final round, with 57.7 per cent of the vote.
Some 12,300 votes were cast in presenter Matt Chorley’s “World Cup of Best PMs We Never Had”.
Mr Corbyn beat his predecessors Ed Miliband and John Smith, as well as ex-Lib Dem leader Paddy Ashdown, and Conservative former chancellor Ken Clarke in the online poll.
Writing in The Times Red Box email briefing before the final on Monday, Mr Chorley said: “It is a title few really want. Actually being the prime minister, even a bad one, is surely better than never quite making it.
“But plenty of people have been dubbed the ‘best PM we never had’ over the years. So as it is a bank holiday weekend, I decided to put the idea to the test to see if we could agree on a single name. As if.”
Veteran left-winger Mr Corbyn became Labour leader in 2015, a result which marked a fundamental change of direction for the party.
He was leader through two general election defeats, the last of which saw seats which had been Labour for generations turned blue as the party’s hitherto impregnable “red wall” crumbled in the face of the Tory advance.
Sir Keir Starmer was named as the new Labour leader in April.
Sir Keir was voted into the top job after beating Wigan MP Lisa Nandy and shadow business secretary Rebecca Long-Bailey.
Angela Rayner was declared winner of the deputy leadership race after winning 52.6 per cent of the vote.
Speaking after being voted leader of the opposition, Sir Keir tweeted: “It’s the honour and privilege of my life to be elected as leader of the Labour Party.
“I will lead this great party into a new era, with confidence and hope, so that when the time comes, we can serve our country again – in government.”