Nuno Espirito Santo’s side know they must win the competition to return to Continental action next term, after failing to qualify for the Europa League through their seventh-place Premier League finish.
In the Greek Super League, Olympiakos won the title by 18 points.
The first leg between the sides ended 1-1 in March.
Here’s all you need to know before kick-off.
When is it and what time is kick-off?
The match will begin at 8pm BST on Thursday 6 August at Molineux.
How can I watch it online and on TV?
The game will be broadcast live on BT Sport 1, BT Sport Extra 1 and BT Sport Ultimate.
Subscribers can also stream the match on the BT Sport website and app.
Wolves: Patricio, Boly, Coady, Saiss, Doherty, Jonny, Moutinho, Neves, Traore, Jimenez, Podence
Olympiacos: Allain, Elabdellaoui, Ba, Casse, Tsimikas, Guilherme, Camara, Bouchalakis, Masouras, Valbuena, El Arabi
It’s all-or-nothing for Wolves with European football in 2020/21 now: win this competition and they get Champions League, or don’t win and get nothing. It’s a good incentive to progress.
Wolves 1-0 Olympiakos (agg 2-1)