TVNZ has complained to Facebook after the publication of weight-loss ads using stars such as Petra Bagust, Toni Street and Shavaughn Ruakere.
The two Breakfast presenters and Shortland Street actress' images appear in separate advertisements for gyms and a beauty product which claim 13kg can be lost with "two simple steps".
TVNZ spokeswoman Megan Richards said the broadcaster had been aware of the issue for several weeks, although the bogus ads appeared to have evolved recently.
Half a dozen gyms including the national chain Les Mills have been promoted by the ads, while earlier ads were linked directly to the product Duocleanse. Clicking on the link takes the user to the promoted gyms' websites but Ms Richards said all had denied having anything to do with the ads.
TVNZ's legal team had asked the social media giant to remove the ads as it was unpleasant for its stars and clearly a breach of copyright.