The opening two days involve medical and physical testing, with the team coming together for full training on Thursday morning at their Hilsea training base.
We’ve dipped into the picture archives to look at first days of Pompey pre-season training from the past, with a host of familiar faces in action.
Hope you enjoy the trip down memory lane far more than those players partaking in them...
13. June 2018
Dion Dohonue; Jamal Lowe; Jack Whatmough; Adam May and Gareth Evans are back in for Pompey pre-season training in June 2018. Picture : Habibur Rahman Photo: Habibur Rahman
14. June 2017
Triallist and future, Luton, Barnsley and Charlton keeper Harry Isted in action on the first day of Pompey pre-season in June 2017 Photo: None
15. July 2010
David Nugent and Marc Wilson on the first day of training in July 2010. Picture: Robin Jones Photo: Robin Jones
16. June 2018
Nathan Thompson; Lee Brown and Conor Chaplin back in the swing of pre-season in June 2018. Picture : Habibur Rahman Photo: Habibur Rahman