The Group C clash in Piraeus will pit the Ligue 1 champions against the Greek Super League winners, and although PSG will be heavy favourites, it is easy to forget that they have little Champions League experience as a club.
PSG will take heart from the fact they reached the quarter-finals last season though, as they enjoyed a successful campaign that saw them win their first Ligue 1 title in 19 years.
They could consider themselves unlucky to be knocked out on away goals by Barcelona in the last eight, and new manager Laurent Blanc has added further quality to an already excellent squad in the close-season.
Edinson Cavani, Marquinhos and Lucas Digne have all arrived in the French capital and PSG have started the season well, winning three of their five league matches and drawing the other two.
PSG warmed up for their trip to Greece with a 2-0 win over Bordeaux on Friday despite a poor preparation, caused by the international break.
Blaise Matuidi and Lucas Moura scored for the winners, but manager Laurent Blanc was unhappy at the fact several of his players only arrived in France the night before the match.
And to compound Blanc's misery, defender Alex suffered a thigh injury in training on Saturday that will rule him out of this fixture.
Injury doubts still linger over Jeremy Menez (back) and Javier Pastore (foot) ahead of the match.
Experienced Champions League outfit Olympiacos will be hoping to improve on last season's performance, when they were knocked out in the group stages.
That was despite them winning three Group B fixtures, two of which came against Montpellier, while they also defeated Arsenal 2-1 at home.
Olympiacos have a mixed record against French opposition, winning 10 of their 26 Champions League fixtures against them.
After a busy close-season, Olympiacos' squad is barely recognisable to last year's, with Javier Saviola and Vladimir Weiss heading the arrivals.
Only eight players registered by Olympiakos for last season's group stage will be involved in the competition this season.
Olympiacos have started their league campaign in superb fashion, winning all four matches, with Konstantinos Mitroglou's six goals helping them to the top of the table.
But they will face a very different test on Tuesday as Blanc's PSG come to town expecting a result.
