Winger Elito, 22, joined the Daggers in the summer of 2011 following a successful loan spell, while midfielder Saunders, 23, penned an 18-month agreement in February 2012, although his contribution was cut short by an ankle injury last term.
Boss John Still told the club's official website: "Medy is a player we know very well. I think his performances this season have been very consistent and I am hoping to see more of the same. He has terrific ability and at his age we think we can improve him and make him a better player.
"Matt had a great grounding as a youngster at Fulham. Unfortunately last year he picked up a bad injury and missed a lot of football.
"He is back now and playing consistently and he is another one that we feel is at a good age and we feel he can get even better. We hope he carries on improving and becomes another top player."
The new contracts come after team-mates Jake Reed and Louis Dennis both also extended their stays at Victoria Road last week.