Messi was suspended by the French champions last week after going on an unsanctioned trip to Saudi Arabia.
The 35-year-old missed last week's 3-1 win at Troyes.
Despite the ban, Messi returned to training on Monday.
PSG need two wins from their final four matches to defend the French Ligue 1 title.
Speaking at the pre-match news conference, PSG boss Christophe Galtier revealed Messi will start against the relegation-threatened side on Saturday.
Galtier told reporters: "I spoke with him [Messi] on Thursday. He is motivated, determined and he wants to win another trophy. Yes, he will be a starter tomorrow."
"He's very eager to win that title," Galtier added.
"With him in the team we'll have to adjust compared to what we did against Troyes. Leo is Leo. I'm not going to go into statistics but when he's with us we have to strike a different balance."
Messi's contract with PSG expires at the end of the season and has been heavily linked with a return to Barcelona.
The World Cup winner has made 28 appearances in the French top flight this season, scoring 15 goals and providing 15 assists.
