The Gossip Girl star - who is married to Hollywood hunk Ryan Reynolds - joins a whole host of A-list L'Oréal ambassadors including Jennifer Lopez, Beyoncé and Eva Longoria.
Gorgeous Blake exudes glamour in the campaign image with swept-back locks, smouldering winged-out eyeshadow and contoured cheekbones.
The blonde bombshell has already had some practice in the world of modelling - she posed up a storm as the face of Chanel's 'Mademoiselle' bag collection and Gucci's 'Premiere' fragrance. Impressive!
Talking about her new partnership, Blake said: "I am thrilled and honoured to join the incredible women who represent L'Oréal Paris. From the versatile and motivational brand ambassadors, to all the women who proudly wear L'Oréal Paris each day."
She added: "I grew up with the inspiration of their message: "We're worth it". What an important value to instill in women. That beauty is rooted in confidence. That is key. That is why I'm so proud to be a L'Oréal Paris woman."
As well as swishing her hair and uttering the famous L'Oréal words, Blake is set to start filming romantic drama The Age of Adaline next year alongside actress Ellen Burstyn.
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