Cauley Woodrow opened the scoring with an impressive free-kick from 20 yards, before Harry Cornick added a second late in the contest.
17 players got valuable minutes in their legs ahead of the final pre-season friendly against West Ham United on Saturday, ultimately the biggest takeaway for Nathan Jones.
Avan Jones made his first-team bow on a muggy night at the Weston Homes Stadium, deputising at right-back after impressing for the Development Squad in pre-season.
Pushing high to join attacks, Jones almost found himself with a shooting opportunity in the early stages after Dion Pereira’s cross-shot was deflected into his path, but the hosts were able to clear.
Summer signing Matt Macey was twice forced into action during the opening 20 minutes – first denying Kwame Poku from distance and similarly then Harrison Barrows shortly after.
After absorbing Peterborough’s attacks, Town were devasating at the other end with a fantastic free-kick from Woodrow to open the scoring.
Admiral Muskwe was fouled outside the area and the summer signing curled his second pre-season goal around the wall and past Harvey Cartwright.
Nathan Jones’ side pressed on as the second half began, almost doubling their advantage immediately but Dan Potts couldn’t direct his header towards goal from Pereira’s corner.
Carlton Morris and trialist Max Haygarth were introduced on the hour, the latter in place of Jones who suffered an injury and was unable to continue.
Macey preserved Town’s lead with a fine low stop to deny Sammie Szmodics before he was later replaced by Harry Isted for the final stages.
In the 82nd minute, Cornick made it two with a deflected effort past Cartwright just minutes after coming on in place of Woodrow who opened the scoring.
The home side could and arguably should have halved the deficit with Szmodics through on goal but the midfielder struck the post as Town recorded their first clean-sheet since the 3-0 win against Hitchin Town.
Town: Macey (Isted 78'); Jones (Morris 59'), Lockyer, Potts, Bell (Williams 86'), Pereira; Lansbury (Pettit 80'), Mendes Gomes; Woodrow (Cornick 78'); Muskwe, Jerome (Trialist 60').
Subs not used: Horvath, Osho, Clark, Campbell, Burke.
Goals: Woodrow (27'), Cornick (82')