The South African-born second row has been replaced by Bastien Chalureau, the reports said, with Willemse placed on a standby list should his injury settle and another change be needed during the tournament.
Chalureau made his France debut in November last year and has six caps, the most recent in the 34-17 warm-up win over Fiji last month.
Willemse was set to be a key part of France's bid to win a first World Cup and is not their only significant injury in the build-up to the tournament, which they start against New Zealand on September 8th in Paris.
First-choice flyhalf Romain Ntamack ruptured cruciate knee ligaments in a warm-up game against Scotland and is out of the tournament while prop Cyril Baille and powerful centre Jonathan Danty will miss their Pool A opener at the very least.
