The Back Cats are 14th in the league table but have won three of their last six games, and their manager believes it is vital to get the combative midfielder fit and firing again
The Wearside club have had a disappointing 2012-13 campaign so far, picking up just 25 points from 22 league games and crashing out of the FA Cup to Championship side Bolton on Tuesday night.
However, Cattermole made his first appearance since November after recovering from a knee injury in a 15-minute cameo against the Trotters, and O'Neill believes the skipper will help lead the club away from the drop zone.
"Lee [Cattermole] has been missing for seven or eight weeks and I am hoping he can stay fit for us between now and the end of the season," he told reporters.
"I did think about starting with him [against Bolton], but I was not sure how he would cope physically."
The 60-year-old manager also revealed star striker Steven Fletcher is suffering from illness but should be fit in time for a potentially crucial game against fellow relegation strugglers Wigan this Saturday.
He added: "Steven came in to do a little bit of work and that was when he was feeling ill and we sent him home. I am just hoping he will recover in time for the weekend.
"Fletcher is a big miss for us, but we should be able to cope. The whole idea of trying to get a team and a squad together is that there are going to be good players missing."
Sunderland have picked up three wins from their last six Premier League games, including a memorable 1-0 victory against champions Manchester City at the Stadium of Light.