The Yamaha rider crossed the line more than 10 seconds clear of his teammate Valentino Rossi, with Maverick Vinales on a Suzuki in third.
Lorenzo, who takes over the lead of the 2016 title race from Marc Marquez, was completing a perfect weekend in Le Mans after setting a record-breaking lap in qualifying on Saturday.
The defending world champion enjoyed a serene afternoon at the historic Bugatti circuit, avoiding mayhem behind with no fewer than eight riders parting company from their bikes.
A perfect race for @lorenzo99.#FrenchGP https://t.co/549mXVLn0b
— MotoGP™ (@MotoGP) May 8, 2016