Fernandez's ex-girlfriend Fabiola Yanez, 43, on Tuesday filed a complaint accusing him of having beaten her during their relationship, which ended after he left office in 2023.
In a lengthy post on the X social network, Milei said the accusations against his predecessor highlighted "the progressive hypocrisy" against the "scam that they called 'gender policies.'"
Since taking office in December, Milei has scrapped the national women's affairs ministry and the anti-discrimination agency, and banned the use of gender-inclusive language in the military.
He lashed out at those accusing him and his government of slashing rights and being "sexist, violent and misogynistic."
"As we have maintained for years, the solution to the violence that psychopaths exercise against women is not to create a Ministry of Women, it is not to hire thousands of unnecessary public employees," he said.
"The only solution to reduce crime is to be tough against those who commit it," he wrote.
The scandal surrounding Fernandez, 65, erupted when text messages detailing the alleged violence cropped up in a separate fraud investigation.
Yanez's lawyer, Juan Pablo Fioribello, told the La Nacion+ channel on Tuesday that messages detailing the alleged attacks, with photographic evidence, were found on the phone of Fernandez's private secretary, Maria Cantero.
The phone was being analyzed as part of a probe into influence peddling during Fernandez's administration.
After initially deciding not to press charges, Yanez later contacted the investigating judge "and told him, 'I want to file a criminal complaint. I want to denounce him (Fernandez) for the blows I received from him and the threats I have been suffering'," Fioribello said.
Argentine media reported that Fernandez has been forbidden from leaving the country amid the probe.
Fernandez has denied the accusation.
"The truth of the facts is different" and "it never happened," he said in a statement on the X social network.
He said that for "the integrity" of his children and "Fabiola herself" he would not make any statements and would only provide "evidence and testimony that will show what really happened."
The lawyer Fioribello, who has also represented Fernandez in other matters, said the former president denied hitting Yanez, but admitted the couple had bad arguments.
