PSG have won the Champions League in each of the last two seasons, beating Inter Milan 5-0 in the 2025 final before overcoming Arsenal on penalties in last season's showpiece in Budapest.
A third straight triumph would take them into a select group of teams to have dominated Europe for three consecutive seasons.
"Doing the treble is the objective, but we know it's going to be very difficult and that there will be obstacles in our way," PSG captain Marquinhos said ahead of the new campaign.
Real Madrid achieved the feat under Zinedine Zidane between 2016 and 2018, while Ajax and Bayern Munich also won three successive European Cups in the 1970s.
PSG's transformation under Luis Enrique has been remarkable. After years of failing to deliver in Europe despite huge investment, the French club appointed the former Barcelona and Spain coach in 2023.
They reached the Champions League semi-finals in his first season before going all the way the following year.
The departure of Kylian Mbappe proved to be a turning point. PSG became less dependent on individual stars and developed into a more balanced and aggressive team.
Ousmane Dembele and Khvicha Kvaratskhelia provide pace and attacking threat, while Achraf Hakimi and Nuno Mendes give the team another dimension from full-back.
In midfield, Vitinha has become one of the key figures in Luis Enrique's system, helping PSG control matches against opponents with greater physical strength.
That quality has been tested repeatedly against English clubs. PSG have faced Premier League opposition 18 times over the past two Champions League campaigns and still managed to win the competition twice.
The biggest challenge this season could be keeping the squad fresh.
PSG played 121 competitive matches across the previous two seasons, with only a three-week break between them because of the FIFA Club World Cup. Many of their players have also been involved in major international tournaments.
Enrique has therefore had to carefully manage his squad, particularly in the early weeks of the season.
PSG remain strong favourites to win Ligue 1 and can afford to rotate players domestically as they prepare for the much bigger European challenges ahead.
Their Champions League campaign begins against Slovan Bratislava on Wednesday before the difficulty increases sharply, with Manchester City and Barcelona among their October opponents.
PSG have also made changes to the squad. Bradley Barcola has joined Liverpool, while Goncalo Ramos, Lee Kang-in and Ibrahim Mbaye have also left.
France international Maghnes Akliouche has arrived, while Ferran Torres has joined from Barcelona.
Torres already knows exactly what Enrique demands after working with him during his time as Spain coach.
"He was like a footballing father for me when I played for him in the national team," Torres said after completing his move to Paris.
For PSG, however, the biggest asset remains their manager.
Enrique has signed a new contract that will keep him at the club until 2030, and he insists his motivation has only increased.
"It is the first time I have stayed four years at the same club, and I am more motivated than I was in my first year," he said.
That hunger could be crucial as PSG attempt to achieve something very few clubs in European history have managed.
