Plymouth Albion number eight Kyle Marriot and Loughborough Students flanker Phil Burgess will join Cornish Pirates for next season's campaign.
Marriott, 23, captains Albion, and has also skippered Devon, while Burgess, 21, is top try-scorer for his side, who are leaders of National Two North.
Pirates chief executive Rod Coward said: "Kyle and Phil are two young players with great potential.
"Both will thrive in the environment our coaching staff are creating."
The signings follow that of Nottingham's Ian Nimmo, who will also join at the end of the current Championship campaign.
The Pirates have also confirmed that hooker Dave Ward, lock Ben Gulliver and prop Carl Rimmer are the latest players to extend their contracts at the club, by two years, two years, and one year respectively.