However, fly-half Elliot Bale has left the city club to join National One rivals Moseley.
Plymouth-born flanker Thompson made nine appearances for the club in National One last year, including five starts.
The 25-year-old former Fylde and Sale Academy player moved back to his home city last year to take up a full-time job as a quantity surveyor.
“It was never my intention to go anywhere else,” said Thompson, who came through Ivybridge’s junior ranks.
“Last season was frustrating for me as I picked up a groin injury shortly after getting into the team and on my comeback I rolled an ankle, which put me out for a further two months.”
Thompson, who was battling it out with the likes of Sam Matavesi, Jarrad Hayler, Andy Chesters and Gregory Sebastien for the number seven shirt last season, is hoping for more game-time this coming campaign.
“I am now injury free and looking to make a fresh start,” said Thompson, who was pictured signing his Albion contract on June 7, although the club waited until June 15 to announce it. “After a good pre-season I really want to be challenging for the number seven shirt.
“It looks like Albion will be keeping the bulk of last season’s squad and there is no reason why we can’t be challenging at the top end of the table.”
Albion have also announced that last season’s academy props Curtis Reynolds and Rory Briers have signed contracts with the club. Both were part of the inaugural Devonport Albion College Rugby Academy.
Reynolds, 19, was loaned out to Devonport Services and then Launceston, while fellow teenager Briers gained experience of league rugby with Devon Two’s bottom club Devonport High School Old Boys.
Fellow forwards Rupert Freestone and Sam Matavesi are also expected to re-sign for Albion, along with former Fylde and Redruth lock Todd Prisk. However, it is believed a number of key backs will be leaving.
Club captain and centre Murphy left last week and his departure has been followed by Bale. Others are expected to follow in the coming days.
Fly-half Bale started the season impressively, scoring 28 points in his first three games, but then injured his knee and lost his place to Billy Searle, who has joined Bristol this summer.
Bale’s knee problem troubled him for most of the season but he still made nine replacement appearances, including an inspired performance away at Fylde, before having surgery to solve the problem.
Moseley were keen to boost their fly-half options after losing Glyn Hughes and former Albion player Charlie Foley following their relegation from the Championship.