Gilbert will instead focus on recovering and then training for the Ardennes Classics on his home roads in the Walloon part of Belgium in the second half of April. Gilbert's next race will be Brabantse Pijl on April 12th, which he has won on two occasions in 2011 and 2014. He has won the Amstel Gold Race three times and completed an Ardennes Week Triple in 2011, winning the Amstel Gold Race, Fleche-Wallonne and Liege-Bastogne-Liege.
"Paris-Roubaix has a magnetic attraction on me, but I won't be there this year," Gilbert confirmed via a statement from the Quick-Step Floors team
"I need to take a break, recover properly and then begin thinking of the Ardennes, where I'll be part of a very strong team, together with Julian (Alaphilippe) and Dan (Martin)."
The Quick-Step Floors team will be built around Tom Boonen for Paris-Roubaix as he races for the final time of his long career and targets a record fifth victory.
Gilbert impressed by winning the Three Days of De Panne and then the Tour of Flanders with a 56km solo attack but he has little experience of riding the tougher and rougher French cobbles across the fields of Northern France.
"I've only raced Roubaix once, back in 2007, and for a race like that you need experience," Gilbert said.
"Tom needs all the support he can get in his final attempt there, as a strong team is a very important factor in Paris-Roubaix, and I wish him all the best."
The Quick-Step Floors team thought long and hard about including Gilbert in its squad but decided his ability and experience will be for more useful in the Ardennes Classics.
"Immediately after his splendid Flanders win, the temptation of lining up Philippe at the start was big, especially as he too was thinking of this," team manager Patrick Lefevere said.
"But we sat down, thought this through and decided it's better for him to rest a bit and then return to training for the Ardennes campaign, where his experience and power will be very helpful."