Silva has been out of action since picking up a hamstring injury in a friendly with Napoli back in August.
However, the Brazil centre-back has recently returned to training and is in line to feature as PSG seek only their fourth Ligue 1 victory of the campaign after a run of four draws in their last five league games.
"Thiago Silva is back in the group," Blanc said. "He will be fit to play tomorrow [Friday] against Lens."
However, while Silva is set to make his return, the visitors will again be without talisman Ibrahimovic – absent since the 1-1 draw with Lyon last month - for the clash at the Stade de France in the Parisian suburb of Saint-Denis.
The Sweden striker's campaign has been marred by various injury problems, with the 33-year-old missing out on his country's Euro 2016 qualifiers with Russia and Liechtenstein due to a heel problem.
And, although Blanc says that the former Barcelona, Milan and Juventus attacker is making good progress in his recovery, the meeting with Antoine Kombouare's men will come too early for Ibrahimovic.
"The injury to Ibrahimovic is progressing well," Blanc added. "However, he is not yet able to train with the group and play."
Blanc confirmed that defenders David Luiz and Marquinhos and forward Ezequiel Lavezzi are also unavailable for the game at France's national stadium.
With Ibrahimovic and Lavezzi unable to play, Blanc expects striker Edinson Cavani to deliver against a side that sits 18th in the French top flight.
"Cavani has worked a lot," Blanc said. "He has made 10 exceptional days. I expect him to confirm that in the match."