Appearing on BBC’s Newsnight on Tuesday, Mr Osborne admitted the Conservative Party ‘did get things wrong’ in the lead-up to the referendum.
The now editor of the London Evening Standard was a prominent figure in the Remain campaign.
EU membership supporters explained the benefits of EU membership ‘too late in the day’, he said, and failed to communicate the value of immigration.
He said: “I think we were wrong to play into the debate that everything that Brussels did was a challenge and a battle and was wrong.
“On immigration we were promising targets that we couldn’t deliver and that then led to a debate about how you might deliver those targets… we definitely contributed to that argument.”
READ MORE FROM YAHOO NEWS UK:
Two teenagers arrested over hit-and-run collision which left boy, 3, fighting for life
Being overweight or underweight could knock four years off your life expectancy
‘Once-in-a-lifetime’ video captures actual moment meteor explodes in the sky
Dad who sent smiling Snapchat picture of son to mother before beating him to death jailed for life
In pictures: The animal species in fastest decline around the world
Mr Osborne said he had worked hard ‘in the national interest’ during his time in office in the face of a hung parliament and faced with the ‘gigantic financial crash’.
He said: “Ultimately the country grew and jobs were created and we avoided the calamitous situation that a lot of European countries found themselves in this period.”
The former Chancellor was a key ally of David Cameron, but has previously admitted he was not in favour of an EU referendum and only supported it out of loyalty to Cameron.
Labour MP Barry Sheerman criticised Mr Osborne and former Prime Minister David Cameron for ‘running away from their responsibilities’ when they lost the EU referendum.
Speaking during the Commons Budget Resolutions debate, the MP for Huddersfield said: “I know that what we’re moving towards is a disaster for their living standards, their health standards and everything else that touches their lives over these coming years. This is a year of crisis…
“This is going to be the next crisis where we need people there at the Despatch Box who actually take on their role as leaders.
“Not people who were there as Prime Minister and Chancellor and when they lost the referendum ran away from their responsibilities, ran away from the leadership.
“Where are they now, in the Evening Standard I suppose, in their man cave writing their memoirs.”