The former Man City captain is thought to be available for around £2.5m with Pompey looking to freshen up their squad after a season of struggle last time round.
Villa are in desperate need of reinforcements with current central defenders Curtis Davies and Zat Knight illustrating that they are not up to the job of replacing the retired Martin Laursen.
At 31, Distin certainly has the experience required to strengthen the back four ahead of what is likely to be a busy campaign spanning four competitions.
Should he sign, Martin O'Neill may choose to pair Distin with error prone Davies but it is understood that the Villa boss wants to bring in more than one defender during this transfer window.
Knight is attracting interest from Bolton and Wolves meaning he may not be a Villa player come the start of the season but many fans will hope he stays as he has the club at heart.