Brenda Moran of Cleveland said Royal Caribbean Cruise Lines has said that she and her husband are no longer welcome on Royal Caribbean, Celebrity or Azamara ships, the Cleveland Plain Dealer reported Sunday.
Moran had posted unflattering remarks about the company on the Internet, the newspaper said.
"If you place negative comments about them on the Internet, you're gone," Moran said. "People should know that a large company is smashing a citizen of the United States for using her First Amendment rights."
Moran calls herself a professional "mystery shopper." On the Web site CruiseCritic.com, she has posted more than 6,000 comments and questions.
Michael Sheehan, the cruise line's spokesman, said the Morans had sailed on six Royal Caribbean-affiliated ships since 2004, and they complained about "a variety of service failures they experienced" on five of them.
"In a small number of cases, we agreed and compensated them appropriately," Sheehan said in a statement.
"In most cases, however, we disagreed. Having concluded that we are unable to meet the expectations of the Morans, we have told them that they would be best served by sailing with another company."