Judge Arthur Engoron's ruling in the $250 million civil trial against Donald Trump and his company orders Ivanka Trump to testify in the case.
Ivanka Trump has until November 1 to appeal the ruling before she can be called as a witness.
Trump's attorneys challenged New York Attorney General Letitia James' subpoena to Ivanka, arguing she should be dropped as a defendant due to statute of limitations issues.
Trump's legal team claimed that the attorney general's office was attempting to harass and burden Ivanka long after the appeals court had mandated her dismissal from the case.
They also argued that the AG's office lacked jurisdiction over Ivanka because she no longer lives in the state.
The AG's office countered that Ivanka Trump, a former White House official, possesses crucial information relevant to their case.
The office wanted to question Ivanka about Trump's former Washington, D.C. hotel, in which she profited from the sale.
They claimed that Ivanka remains financially and professionally connected to the Trump Organization and can be considered a person still under their control.
Ivanka Trump's siblings, Donald Trump Jr. and Eric Trump, as well as their father, are expected to testify in the case as witnesses for both the AG and the defense.
The attorney general is suing Donald Trump for allegedly inflating his assets in financial statements to secure more cost-effective loans and insurance policies, a claim that Trump has vehemently denied, referring to it as a "witch hunt."