Federal prosecutors are probing Democratic Party records related to Assembly Speaker Carl Heastie, The Post has learned.

A former Bronx Democratic Party official was subpoenaed last week to appear before a grand jury with all of the books and records of the party pertaining to Heastie, a law-enforcement source told The Post.

The stunning revelation that one of the three most powerful men in Albany is caught up in yet another federal probe comes months after the corruption convictions of the state Assembly and

Senate leaders, Sheldon Silver and Dean Skelos.

Ischia Bravo, a former executive director of the Bronx Democratic County Committee, would neither confirm nor deny that she had received the subpoena issued by an Albany grand jury.

But she suggested she had been contacted by authorities.

“I think they were just unaware that I was not there anymore so I no longer have records or have retained records,” Bravo said.

She left the party job last year and is now running for the Assembly herself, challenging incumbent Democrat José Rivera.

Heastie, 48, was the Bronx party chairman from 2008 until shortly after taking the speaker position in February 2015 to replace the indicted Silver.

County committees choose and fund candidates, aid campaigns and can pay for political expenses like travel. They must document their finances to the state Board of Elections. The board is based in Albany, the jurisdiction of the US attorney for the Northern District of New York, where the subpoena was issued.

The Bronx committee had $80,000 in its coffers as of July 2015, state records show.

“This is an old story,” said Anthony Perez, executive director of the committee, apparently referring to a Post report last year on a federal probe of the Bronx Democratic machine. “We have nothing to add.”

A spokeswoman for the US Attorney’s Office in Albany declined to comment.

Michael Whyland, a spokesman for Heastie, said, “We haven’t been advised of any investigation, so there is nothing to comment on.”

Heastie has not been indicted and has not faced any charges related to political corruption.

But questions have long swirled around his campaign finances. His campaign committee paid for thousands of dollars in repairs on his personal car and for entertainment at nightclubs and bars, public records showed.

The state’s Moreland Commission on Public Corruption, disbanded in 2014, had targeted his spending. His campaign bank-account records were reportedly subpoenaed by Moreland probers.

The commission’s files were turned over to Manhattan US Attorney Preet Bharara.

The Post reported last year that Heastie paid his former girlfriend and baby mama, Alvita “Lan” Robertson, $2,500 in campaign money to design a Web site. His campaign made two payments of $1,250 to her in 2011. Robertson, a model, subcontracted the work to someone else and still got paid.

Heastie’s latest financial disclosures show that in 2014, he owed up to $50,000 on one credit card and up to $20,000 on another. He also owed up to $20,000 to Lending Club for debt consolidation.