Treve's preparations to win a record Prix de l'Arc de Triomphe began with success in the Prix Corrida.
The five-year-old, who could become the first horse to win the Arc three times in October, made easy work of the mile and a quarter at Saint-Cloud.
In her first outing since 2014's Arc success, the Criquette Head-Maarek-trained mare stayed with the pack until moving clear after the final turn.
Treve's next entry will be the Grand Prix de Saint-Cloud on 28 June.
Owner Sheikh Joaan had been expected to retire Treve at the end of last year, but opted to bring her back for another campaign.
|BBC Sport's Cornelius Lysaght|
|Having been beaten in her first two races of 2014, and knowing that an attempt at an unprecedented third Arc win in the autumn is the over-riding priority, expectations were not excessively high for Treve here.But she was quite superb, moving magnificently through the race, before positively slamming We Are, a Group One race winner who had the advantage of race-fitness. It looks like it will be very hard to stop Treve making history in the Arc on 4 October.|
"She did everything I thought she would so I am delighted," said Head-Maarek.
"She will improve a lot on that and there's so much to look forward to, with the Grand Prix back here the next step."
The Arc, Europe's premier middle-distance event, will be held at Longchamp on Sunday, 4 October.