Fernando Vazquez's side have been fighting a relegation battle all season but will secure survival in the Primera Division, which seemed unthinkable two months ago, if they can secure the three points at their home, Riazor.
Sociedad, meanwhile, are aiming to qualify for the Champions League for the first time in a decade.
Philippe Montanier's side were in the driving seat to finish fourth in the league with five games remaining, but two draws and a defeat in their last four games mean that they must not only win in Galicia, but also hope that Sevilla can do them a favour by beating or drawing with fourth-placed Valencia.
Vazquez told reporters he was optimistic about his side's chances of avoiding the drop, even though it has been said that Deportivo have the toughest opponents of the bottom four sides.
In Depor's favour is the fact that, as well as having the advantage of playing in front of their own fans, they are the only team still fighting for survival that depends on just their own result.
He said: "Our rivals say we have the hardest game. That's one way of looking at it, because they will have to be very optimistic, because their only hope is that we slip up.
"As I've said to my players, I wouldn't swap our places with Celta, Mallorca or Zaragoza. We have the initiative, that's fundamental. Our fate is in our own hands, and that is a tremendous advantage."
He also gave one last rallying cry: "We have to think that we are going to win, that we cannot lose at Riazor. We have a great chance of doing it. The players and the fans must arrive with this positive energy."
The match will be Real Sociedad coach Montanier's final for the Basque outfit, as he is going to take charge of French side Rennes next season.
In his final pre-match press conference, the coach explained how proud he was of his team's achievements, and revealed he was still hopeful of getting fourth spot.
"It gives me tremendous satisfaction to see how much this team has progressed, both in attitude and mentality," he said.
"The squad have been incredible and tomorrow (Saturday) we will go all out for fourth place. We know it'll be difficult, but with these players, anything is possible."