Harverson will start at Clarence House in February next year as communications secretary, a newly-created position that effectively sees him replace Mark Bolland as HRH The Prince of Wales's chief spin-doctor.
Press secretary Colleen Harris, who is responsible for the day-to-day running of the press office, will cease to work at Clarence House at the end of next week.
Assistant press secretary Patrick Harrison will replace Harris on an interim basis and 'all other decisions [as to the appointment of a permanent replacement for Harris] will follow on for this', according to a Clarence House spokeswoman.
The Prince of Wales's private secretary Sir Michael Peat said Clarence House had been impressed by Harverson's 'friendly and down-to-earth approach'.
Harverson joined Man United in December 2000 from a role as sports writer at the Financial Times.
His departure from Man United comes just seven weeks after CEO Peter Kenyon, who hired Harverson, quit to take the same role at rival Premiership club Chelsea.
Bolland ceased to work for Prince Charles in January and now runs his own agency, Mark Bolland & Associates.
However, he continues to provide ad hoc PR advice to Charles's partner Camilla Parker Bowles.
Harris's resignation was announced in July, when she said: 'The hours here are quite punishing. I want to be at home when I am awake'.