The Olympic road race silver medallist won the opening World Cup round, the Ronde van Drenthe, then placed second in the two subsequent events, the Trofeo Alfredo Binda and Tour of Flanders.
And another second place finish, a couple of bike lengths behind France's Pauline Ferrand-Prevot, maintained her lead of the overall World Cup standings with five races remaining. Sweden's Emma Johansson remains her nearest rival.
World and Olympic road race champion Marianne Vos was sixth while Armitstead's British team-mate Emma Pooley, who won the race in 2010, was seventh in her first appearance of the season.
Flèche is famed as one of cycling's toughest one day classics and the women's race shares the same finish as its men's counterpart - located on top of the Mur, or 'Wall', at the town of Huy, located above the valley of the Meuse.
The next round of the World Cup series is in China next month, though Armitstead will focus on racing in the inaugural five-day women's Tour of Britain, which starts in Oundle on May 7.
© Sportsbeat 2014
- Sports & Recreation
- Trofeo Alfredo Binda
- Emma Johansson
- Marianne Vos
- Ronde van Drenthe
- Emma Pooley