"This meritless lawsuit threatens to chill the speech of those who dare to publish content that the President does not like," lawyers for the Journal and its billionaire owner Rupert Murdoch wrote in a court filing.
A White House spokesperson referred to Trump's personal lawyers on the case, who did not immediately respond to a request for comment.
Trump filed the lawsuit on July 18, as his administration faced criticism from its conservative base and congressional Democrats over its handling of the Epstein case.
The Justice Department in early July said it would not make public files from its sex trafficking investigation into Epstein, reneging on earlier promises from Trump and his allies to do so.
The lawsuit is one of several Trump, a Republican, has filed in recent months against major media outlets over reporting he has characterised as unfair or false. That has led to concern among Democrats and press freedom advocates that he is seeking to use defamation cases to quell critical coverage.
To prevail in defamation cases, public figures like Trump must meet the "actual malice" standard, meaning they must prove not only that a public statement about them was false but also that the media outlet or person who made the statement knew or should have known it was false.
In his lawsuit, Trump called the alleged birthday greeting "fake" and sought $US10 billion in damages for what he called damage to his reputation.
News Corp's Dow Jones, the Journal's parent, defended the accuracy of its reporting. Democrats in the US House of Representatives on September 8 made public a letter that contained text of a purported dialogue between Trump and Epstein within a sketch of the silhouette of a naked woman.
The White House said the signature on the letter was not Trump's. The House said it had received the letter, part of a collection of greetings for Epstein's 50th birthday compiled by his longtime associate Ghislaine Maxwell, from lawyers for Epstein's estate.
In asking Miami-based US District Judge Darrin Gayles to dismiss the case, the Journal's lawyers said the letter released by Congress was "identical" to the one described in the article.
"The Article is true," the lawyers wrote.
Epstein died by suicide in 2019 while in jail awaiting trial on sex trafficking charges. He had pleaded not guilty.
Maxwell is serving a 20-year prison sentence for helping recruit and groom teenage girls for Epstein to abuse. She had pleaded not guilty, and has asked the US Supreme Court to overturn her conviction.
Trump's lawsuit against the Journal came after he reached a $US16 million settlement with CBS News' parent Paramount Global over the editing of an interview with former Vice President Kamala Harris on 60 Minutes.
Earlier this month, Trump sued the New York Times over articles he said were aimed at sabotaging his chances in the 2024 election.Â
Last week, a federal judge threw out Trump's $US15 billion lawsuit against the Times because the complaint lacked a concise statement of why Trump should win. The judge gave Trump 28 days to file an amended complaint.
