Edinson Cavani and Kylian Mbappe were absent – though the latter was involved in a pre-match World Cup presentation at the Parc des Princes on Sunday - but Neymar helped ensure a comfortable victory for the champions.
The Brazilian scored early, capitalising on the first of two Brice Samba mistakes to slot in a Christopher Nkunku pass, with Adrien Rabiot adding a second from Angel Di Maria's excellent assist before the break.
Gianluigi Buffon's Ligue 1 debut was mostly uneventful, the former Juventus and Italy goalkeeper able to keep a clean sheet after Stef Peeters hit the post with a free-kick in the second half, while Timothy Weah capitalised on another Samba error to complete the scoring in the 89th minute with his first Ligue 1 goal.
Neymar opened his 2018-19 account inside 10 minutes, finishing off Nkunku's throughball after a disastrous pass out by goalkeeper Samba.
A second PSG goal inevitably arrived in the 35th minute, Di Maria dancing clear of the defence through the right channel to square a low cross that Rabiot could hardly miss from close range.
Buffon, who became PSG's oldest ever Ligue 1 player, was surprisingly busy in the first half, the 40-year-old beating away a powerful effort from Malik Tchokounte before reacting in mid-air to tip away a cross that deflected off team-mate Thiago Silva.
The goalkeeper was helpless as Caen went close to getting on the scoresheet in the 52nd minute, though, as a fine free-kick from Peeters bounced off the inside of Buffon's right-hand post.
Although Neymar appeared determined to add more goals after a disappointing World Cup with Brazil, it was his replacement who added a late third.
Samba had done well to tip a Weah shot on to the post but then horribly lost control of a backpass, allowing the substitute to tap in from close range and get Tuchel's men up and running.
What does it mean: Promising signs for Tuchel's men
After a 4-0 demolition of Monaco in the Trophee des Champions secured early silverware for Tuchel at PSG, the German will have been reasonably satisfied with what he saw in the league opener. Forced into picking a youthful side in the absence of some star names, Nkunku was among those to impress again after being given opportunities with the first team in the International Champions Cup.
Pat on the back: Nsoki a star in the making
A pair of Stanley N'Soki assists in the thrashing of Monaco caught the eye, and the teenager impressed against Caen with his calm use of the ball on the left flank. Yuri Berchiche's departure to Athletic Bilbao creates a spot in the first team as cover and competition for Layvin Kurzawa. Nsoki is poised to step up to fill the void, with the 19-year-old completing over 90 per cent of his passes.
Boot up the backside: Samba error ends Caen hopes early
It is hard enough for away sides at the Parc des Princes without PSG being gifted a goal in the opening stages. What Samba was thinking when he played a pass straight to Nkunku is hard to guess, but the goalkeeper's mistake provided Neymar with the opener and set the tone for an uncertain performance from the 24-year-old in what was only his sixth Ligue 1 appearance.
Key Opta stats
- PSG have won 69 per cent of their games in Ligue 1 against Caen (24/35), their best win percentage against a top-flight team they’ve faced more than 10 times.
- Caen are winless in their last 15 Ligue 1 games against PSG (D4 L11), with their last victory coming in April 2008 (3-0).
- Neymar has scored 20 goals in 21 Ligue 1 games, including 13 goals in 12 games at the Parc des Princes.
- Timothy Weah is the first player to score after his father for Paris in Ligue 1 after Jean & Youri Djorkaeff.
- PSG have scored two or more goals in 23 of their last 25 home games in the league.
Guingamp host PSG on Saturday as Tuchel looks to continue a promising start, while Caen will hope for a better result in their first home game of the season against Patrick Vieira's Nice.