The Argentine sensation, who was signed before the start of the season for a French record 42-million euro fee from Palermo, is expected to play after a three-week injury layoff that coincided with PSG's lack of creativity in midfield.
Pastore's presence was sorely missed when his team could only manage a goalless draw at Nice last Saturday with PSG dropping their first points since Carlo Ancelotti took over from Antoine Kombouare at the end of December.
"We must be more efficient in attack," Ancelotti told reporters on Wednesday.
"What we showed would not be enough against Montpellier."
"We need to use the whole width of the pitch because our opponents can too easily contain our three offensive players," he told a press conference earlier this week.
"I think he [Pastore] will be ready for the Montpellier game," Ancelotti added.
Montpellier will once again rely on Olivier Giroud, the league's top scorer with 16 goals, who on Wednesday hinted he could stay next season if the side were to qualify for the Champions League.
"I want to play the Champions League and whether Montpellier are qualified for it or not will be a big factor in my decision," the France striker told a news conference.
"We must quickly regain some balance," coach Rudi Garcia warned.
