The South Africa international has been out of action with a knee injury since last month's 4-1 FA Cup defeat to Arsenal.
Everton are just four points adrift of fourth-placed Arsenal in the race for the final UEFA Champions League place ahead of the meeting between the two sides at Goodison Park on Sunday.
Pienaar will be unavailable for the visit of Arsene Wenger's men, but Martinez revealed that the former Ajax, Borussia Dortmund and Tottenham man could soon return for the Premier League run-in.
"Stevie is doing well," Martinez told the club's official website. "Obviously it was a real setback to lose him.
"Recovering from (an injury to) the cartilage in the knee can be tricky but at the moment he is recovering well.
"I'm hopeful that we can see Stevie before the season ends and that is where the focus goes.
"But he's been lively and has been working well. It is going to be really positive for us if we can get him back before the season ends."
Everton, who earned a 1-1 draw at the Emirates Stadium in December, have a game in hand on Arsenal.
