Brooklyn District Attorney-elect Ken Thompson is happy to be taking Charles Hynes’ seat next week — but he says the veteran lawman can keep his throne.

Thompson transition aide Arnie Kriss has told a Hynes staffer that Thompson wants the toilet seat in the district attorney’s private bathroom replaced, said a source close to the outgoing DA.

“Kriss said Thompson wants a new toilet seat installed in the DA’s private bathroom because he doesn’t want to sit on the same toilet seat that Hynes sat on,” the source said.

“You’d think he’d be worried about running the office, not about a toilet seat.”

Kriss made the unusual request at a transition meeting last Thursday, a source said.

“If you asked de Blasio if he’s changing Bloomberg’s toilet seats, I bet the answer is no. Who the f- -k thinks of changing the toilet seat? It’s bizarre,” said the source, adding both the seat and the toilet were replaced about six months ago and are almost brand new.

Another source confirmed Thompson’s potty plan and said the other requests were for routine tasks such as cleaning offices.

“As he’s ascending to the throne, he wants to make sure it’s his throne,” the source said.

The private bathroom connects to the DA’s wood-paneled office on the 19th floor of the Downtown Brooklyn building. It has a phone and can function as a safe room in an emergency, sources said.

Hynes spokesman Jerry Schmetterer declined to comment.

Thompson spokesman James Freedland brushed aside the issue, calling it a “nontroversy.”

A source close to Thompson said, “Certain office facilities have not been left in acceptable condition, and the incoming DA is cleaning up the office on multiple fronts.”

On New Year’s Day, Thompson will take over the office Hynes has held for 24 years.

The toilet to-do is the latest in a series of dust-ups between the two men since Thompson beat Hynes in the Democratic primary in September and again in the general election in November.

First, Hynes trashed Thompson’s ties to disgraced ex-Democratic Party boss Clarence Norman. Thompson denied Norman, whom Hynes sent to jail for corruption, aided his campaign.

And Thompson tried to block Hynes from paying his retiring rackets chief for unused vacation days that amount to more than a year’s pay. Hynes stood firm.