The Dutchman has spent the past eight seasons with Quick-Step Floors, winning Paris-Roubaix, the Tour of Flanders and E3 Harelbeke during his time with the Belgian WorldTour team.
In a press release on Direct Energie's website, Niki Terpstra said of the move: "I was impressed by Direct Energie this season during the Flanders Classics where the riders of the team were systematically involved in the race.
"Damien Gaudin, Sylvain Chavanel and Adrien Petit were among the great animators in the Belgian campaign. I also liked their aggressive style at the Tour de France."
In addition to strengthening the French team's Classics capabilities, the versatile Dutchman will also bolster the squad in stage races and the Tour de France.
Although in the latter stages of his career, Terpstra has already had a successful 2018 with two of his biggest career victories in the Tour of Flanders and E3 Harelbeke, as well as a solo victory at Le Samyn.
Terpstra's ambition looks set to continue with Direct Energie, with the four-time Dutch national road race champion aiming for more Classics success.
"I dream of bringing Direct Energie a prestigious victory at a big Classic. And, above all, to win a stage at the Tour de France. I have tried in the past a lot, but joining a French team may be the answer."
Direct Energie team manager Jean-René Bernaudeau added: "Welcoming a rider of the calibre of Niki is an honour for Direct Energie. He has character and ambition, like us.
"I am happy to see that he shares our values and wishes to be part of our project. We are very vigilant when we recruit riders who do not come from the Vendée region, but, with Niki, I'm sure we have made the right choice."
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