"I acknowledge that these false statements were very harmful and hurtful to Mrs. Trump and her family, and therefore I sincerely apologize to Mrs. Trump, her son, her husband and her parents for making these false statements," the blogger, Webster Tarpley, wrote in a statement released by Trump's lawyer.
A lawyer for Tarpley confirmed the accuracy of the statement in an email and said the case had been resolved. Neither side would divulge the amount of the settlement, though Trump's lawyer Charles Harder called it a "substantial sum."
Trump, who is married to U.S. President Donald Trump, filed the lawsuit last year against both Tarpley and the Daily Mail, a British tabloid, after the newspaper published an article that falsely alleged she had worked for an escort service.
The article cited a Slovenian magazine's report that a modeling agency with which Trump worked in New York in the 1990s also served as an escort business.
Last week, a Maryland judge dismissed the claims against the Daily Mail on jurisdictional grounds while allowing the lawsuit to continue against Tarpley. The settlement ends that case.
On Monday, Trump filed a new $150 million lawsuit against Mail Media, the Daily Mail's owner, in New York state court, claiming the article had cost her millions of dollars in potential business.
Trump had a "unique, once-in-a-lifetime opportunity" to launch numerous product lines, including jewelry, apparel, shoes and cosmetics at a time when she is "one of the most photographed women in the world," according to the new lawsuit.
A spokesman for the Daily Mail did not immediately respond to a request for comment on Tuesday.
Harder, Trump's lawyer, has represented several celebrities and won a $140 million invasion of privacy verdict for wrestler Hulk Hogan against the now-defunct Gawker last year.
Trump, a native of Slovenia, moved to the United States in the 1990s and in 2005 married Donald Trump, who entered the White House on Jan. 20.