The New York Archdiocese has hired former FBI Director Louis Freeh to probe sex abuse allegations against Brooklyn Bishop Nicholas DiMarzio, according to a new report.

DiMarzio, 75, is accused of repeatedly molesting Mark Matzek when he was an altar boy and student at St. Nicholas Church and School in Jersey City in the 1970s, according to Matzek’s lawyer, Mitchell Garabedian.

Garabedian took Matzek’s claims public in November, and announced plans to file a lawsuit against DiMarzio.

“We look forward to the filing of the lawsuit so Bishop DiMarzio can have his day in court,” DiMarzio’s attorney Joseph Hayden told the Diocese-owned Brooklyn Tablet. “Bishop DiMarzio is ready, willing and able to defend this lawsuit . . . because the allegation is not true.”

The pope ordered the New York Archdiocese’s Timothy Cardinal Dolan to launch an investigation into Matzek’s allegations in January — an arrangement Garabedian and the National Catholic Reporter have criticized because of the priests’ friendship.

Dolan recently touched on his cozy relationship with DiMarzio on his radio show, “Conversations with Cardinal Dolan.”

“I love the guy, he’s a good friend, he’s never had an accusation against him his whole life,” Dolan reportedly said last month.

“But in November, somebody made an accusation from way, way, way, way, back — 48 years years ago — and, as much as Bishop DiMarzio said ‘This is preposterous, this is ridiculous, this is unjust,’ darn it, we have to take it seriously. We promised we would . . . and I have to as well, and the Holy See does.”

The Archdiocese told The Post in January that it would appoint an outside firm to conduct the probe, and the Tablet reported Wednesday that Freeh had been hired.

Freeh, who served as FBI director from 1993 to 2001, was hired by the Penn State Board of Trustees to probe the Jerry Sandusky scandal. In a bombshell 2012 report, he claimed the school did not do enough to prevent the football coach’s abuse of young boys.