Greg Dyke will step down as Football Association chairman in July after admitting he faces a battle to push through reforms for the governing body.
Dyke had initially said he would stand for a further year in office, but opposition to proposed reforms from many on the FA council and a minority of board members made him change his mind.
The 68-year-old said "more of a conciliatory figure than me" would be needed to pick up the pieces after the battle to get the reforms through. He says there is "inevitable discord" ahead.
Dyke is pushing for an end to the traditional 'blazers' who dominate the council with more women, more fans' representation, more people from ethnic minorities and possibly term limits to reduce the average age.
He would also have had to get the backing of the FA council to stay on for another year until he turned 70, and there was no guarantee of that succeeding.
Dyke read a prepared statement to the FA board on Thursday announcing his decision.
He said: "As you know, in early January I announced I would stand as chairman of the FA for a further year although I wasn't certain this was the right decision for either the FA or me.
"We need a comprehensive change to the governance system there, we need to make it much more representative, we need more women, more people from ethnic minorities, it needs a big change."
"During January, however, as work on options for governance reform crystallised, it became clear to all of us that there wouldn't be a unanimous position on governance reform in the board.
"What now appears to be the case is that there is a majority position on the board for much needed significant reform. I fully support this, but I recognise it is going to be a fight to get through the FA council.
"I had already decided that if no reform was possible I was going to leave anyway this summer, a position I had shared with a number of colleagues.
"What I now see is that even if we get the reform through (which will be a difficult and divisive process although essential), I am probably not the best person to pick up the pieces following the inevitable discord."
Dyke will leave his post convinced his period in office has changed the face of the organisation.
"I think the FA needed changed and I think we have changed a lot, and I think in terms of governance I think it needs significance change, but I have never hidden that," Dyke later told Sky Sports News.
"There is a majority of the board in favour of change, but there is opposition on the board. Whatever happens at the end of it, I think it would be better if someone else took the helm.
"We need a comprehensive change to the governance system there, we need to make it much more representative, we need more women, more people from ethnic minorities, it needs a big change.
"By the summer we will have either got the governance changes through or we won't."
The former BBC director-general has been FA chairman since July 2013, during which time he has become an outspoken critic of FIFA under Sepp Blatter. As well as attempting to modernise the FA, Dyke has also pursued policies aimed at increasing the number of English players in the Premier League.