Ashley Brown has stepped down as chairman of the Pompey Supporters' Trust.
However, he will remain on the group's board as they head into new post-ownership challenges following the Tornante takeover.
In his chairman's report published in the agenda for Thursday's eighth Trust AGM, Brown revealed his decision to step down.
It ends almost six years in the role for the 48-year-old, who has also served on Pompey's club board.
Brown wrote: ‘Having served as chairman for the majority of the last six years it seems an appropriate time to stand aside and begin this new chapter of the Trust under new leadership.
‘I know we have hugely capable people on the board and look forward to working with the new Chair.'
The Trust AGM is to be held on Thursday, September 21, in the Victory Lounge at Fratton Park.
Doors open at 6.30pm for a 7pm start.