Magazine publisher Bauer Media will appeal against a court decision ordering it to pay actress Rebel Wilson $4.5 million in damages for a series of defamatory stories.

Wilson successfully sued the publisher over eight articles printed in 2015 that were found by a Melbourne Supreme Court to have damaged her reputation and marketability in "a huge worldwide marketplace".

It was the largest damages payout ever ordered by an Australia Court.

In a statement today, Bauer Media said it would challenge the $4.5 million figure.

"Bauer Media has today advised that it will be appealing the quantum of damages in the recent defamation judgement," its General Counsel Adrian Goss said in a statement.

"It's important for us to revisit this unprecedented decision on the quantum of damages, which also has broad implications for the media industry."

Wilson had sought $7 million from the Woman's Day publisher but the court was told she was prepared to settle before trial for $200,000.

The actress said the articles were a "malicious, deliberate take-down" of her.

When handing down his findings, Justice John Dixon strongly criticised Bauer Media for failing to properly investigate claims made about Wilson, and for publishing them despite knowing they were false.

"The information was based on a source who required payment and anonymity and whom the editor considered had an axe to grind," he said.

"They repeated the offending allegations when they knew or foresaw that their defamatory slurs would be repeated in the entertainment and celebrity media."