David McDaid has rejoined Derry City after leaving York City, while the Candystripes have also secured the signings of Dean Jarvis and Eugene Ferry.
Ferry is back with Derry after a brief spell in Sunderland where he was playing for Sunderland RCA.
Jarvis was a former Derry City youth player before he moved to Aberdeen in the Scottish Premier Division.
He made his debut for the Scottish club in October 2010 before a move to Institute.
Derry boss Declan Devine said: "It is great to have the two lads back after their short spell away from the club, I feel that with these three signings add great depth and strength to our squad especially with the very busy period we are now entering into.
"Eugene has always been a great asset to us and will push the rest of the lads on for a place in the side.
"David was our top goalscorer last season and again his signing adds another attacking option for us. it will mean that we will have great competition for places amongst our strike force and that can only be good for the club.
"Dean has been on the clubs radar now for a couple of season and I am glad that we have finally been able to get secure his signature. He is still a very young lad but despite his age he has some very good experience already.
"Having played for a couple of season at Aberdeen and then returning to Institute he has shown that he is more than capable to play at this level."