A glum-looking Howard Redmond — the disgraced NYPD inspector who headed former Mayor Bill de Blasio’s security detail — surrendered to Manhattan prosecutors on Wednesday to face obstruction charges.

Redmond is expected to be charged with blocking a city probe into the former mayor’s alleged misuse of his security detail during his quixotic 2020 presidential bid.

He turned himself in at Manhattan Criminal Court around 8:37 a.m., wearing a dark suit and a blue-pattern tie, and accompanied by his lawyer, Louis La Pietra.

The Manhattan District Attorney’s Office has been considering criminal charges against Redmond since 2021 after the city’s Department of Investigation determined that he “actively obstructed and sought to thwart” the investigation into de Blasio’s spending.

The veteran cop was suspended from the NYPD without pay July 11 as the charges hung over his head. He was later “dismissed” from the department, police said Wednesday without providing any additional details.

According to a 49-page report released in October 2021, the NYPD shelled out $319,794 for the department’s security detail to accompany de Blasio as he traversed the country during his longshot campaign — including to attend a Red Sox game.

Former DOI Commissioner Margaret Garnett said at the time that the mayor’s son, Dante de Blasio, even used his dad’s security detail as a “concierge service.”

Members of the detail also “occasionally” chauffeured de Blasio campaign staffers as well.

Redmond, who headed up the then-mayor’s detail, was the only person in the probe to be referred to prosecutors for potential criminal charges by the DOI, which found he “actively obstructed and sought to thwart” the investigation.

The DOI said Redmond refused to hand over his cellphone for months, and only did so after he was ordered to by a supervisor.

He allegedly first destroyed the phone “under the guise of receiving an upgraded device,” according to the DOI report.

The report also accused the head of the Executive Protection Unit of ordering subordinates “to impede the NYPD from getting access to EPU communications.”

“DOI has concluded that the NYPD inspector in charge of the First Family’s security detail actively obstructed and sought to thwart this investigation, frustrating DOI’s efforts to learn the full facts regarding these allegations,” the report said.

Redmond is expected to be arraigned on the criminal charges later Wednesday.