She’s a real “troublemaker.”

The prison worker suspected of helping two killers escape was caught in the act having sex with a colleague at her old job — breaking up both their marriages, it was revealed Wednesday.

Joyce “Tillie” Mitchell, 51, engaged in the affair while working at an upstate slipper factory — and her ex-hubby who was rocked by the tryst said Wednesday he wouldn’t be surprised if she also had slept with an inmate.

“Sure she cheated on me, so I could see her falling for someone in prison,” Tobey Premo told the Daily Mail.

The affair that broke up Premo’s relationship with the lusty Mitchell was the subject of wild workplace gossip, as it happened outdoors near the factory in upstate Bombay.

“There were reports of people having sex on the railroad tracks outside the factory,” a former co-worker told the Mail, adding that Mitchell “was the one who was gossiping the most about it.”

When workers “finally caught the couple in the act — it was Lyle and Tillie,” the source added, referring to Mitchell’s current husband, Lyle Mitchell.

Premo’s other former wife told The Post that Joyce’s dalliance with Lyle caused a melee in a workplace restroom between the two men.

“She was cheating on him with Lyle,” said Helen Premo. “They all worked together — Tobey found out. When I met him [Tobey], he had been on probation [for] beating [Lyle] up in the bathroom.”

Another former co-worker, Nancy Hewitt, said Joyce was “always a troublemaker.”

“She was quiet up to a point, but she would always be the one who would be trying to get people into trouble,” Hewitt told the Mail.

“I know for a fact that a friend of mine who works at the prison told the authorities there not to hire her because she’d cause trouble — but they did, and now look what happened.”

Law enforcement sources have said convicted killer Richard Matt wooed Joyce behind bars while she supervised the sewing shop at the Clinton Correctional Facility in Dannemora.

She allegedly was supposed to meet Matt and fellow killer con David Sweat in a car when they broke out of the maximum-security slammer, but she suffered a panic attack and bailed.

An ex-prison colleague of Joyce told The Post people “knew this was going to happen” because she got too close to the inmates.

“She would give too much information. She was naive in the way she would answer the inmates,” the colleague said.

Meanwhile, at the end of the fifth day of the manhunt for the escapees, police blocked a major highway near the prison at about midnight to investigate a lead.

Residents near Route 374 and Trudeau Road in Cadyville were told to stay indoors as police swarmed the area.

Additional reporting by Bruce Golding and Joe Tacopino