Jimmy Davies, 71, is stepping down as boss of Waterloo Dock AFC, in the Liverpool County Premier League.
Mr Davies, who first took charge in 1963, said he had enjoyed managing "tremendously".
He added that life in the grassroots game had been "proper football".
Mr Davies's claim to be the longest-serving manager in England has been verified by The Football Association.
He said he had "made the bold announcement it was going to be my last year ahead of our AGM, although I will still be on the committee" and added that "time moves on [and] the modern age is catching up on me".
Mr Davies will have been in charge for 24 more years than Sir Alex Ferguson, who recently announced he was stepping down at Manchester United after 26 years, but said there were not many similarities between their tenures.
"I don't think Fergie gets involved in washing football kits like my wife does," he said.
Waterloo Dock AFC was formed by a group of friends who worked on Liverpool docks in 1963.
Mr Davies, who has logged every game's appearances and scorers ever since, said he had played "early on but after six weeks, the lads found me out and, trying to be nice, said 'you can go and be our manager'".
"It was purely by accident."
Mr Davies's tenure has seen the club win more than 70 trophies.
Waterloo Dock's best-known player was striker John Durnin, who started his career with the side before being sold to Liverpool for £500 in 1986.
Mr Davies's last game as manager will be on 28 May.