With injury to Luke Roberts, manager Tommy Killick felt he needed a little bit of experience to enhance the squad for the start of the 2017/18 season.
Oxlade-Chamberlain (pictured), 19, and the brother of Arsenal and England`s Alex, has yet to appear for Pompey first-team, but has had loan spells with Wimborne Town and Salisbury FC in the Evo-Stik South West and Eastbourne Borough in the National League South.
Poole-born Bedford only recently penned a one-year professional deal with Portsmouth, graduating from the Fratton academy set-up.
He featured in the FA Youth Cup last season, as well as playing a part in the reserves' much-lauded Premier League Cup run as they overcame all the odds to reach the semi-final stage.
With the support from Kenny Jackett at Pompey, both Bedford and Oxlade-Chamberlain will add a little to Poole’s start to their second season in this league.
It will also allow some of the evolving youngsters a little more time to adjust to life within the first-team.