Disgraced politician Dean Skelos deserves to be punished twice when he’s sentenced to prison next week — once for corruption and once for lying on the witness stand, Manhattan federal prosecutors said Friday.

In a document filed ahead of ­Skelos’ Oct. 24 sentencing, prosecutors said the Long Island Republican “lied repeatedly” when he took the witness stand at his 2018 retrial and told the jury that he never “intended” to pressure companies into giving son Adam do-nothing jobs and consulting gigs.

They asked that Dean — once one of the most powerful men in Albany along with Gov. Cuomo and ex-Assembly Speaker Sheldon Silver — get at least 6½ years in the clink, which is 18 months more than the five-year sentence imposed on him after his first trial.

Dean and Adam were first convicted in 2015, but the case was tossed on appeal — paving the way for the politician to take the stand in his own defense in July.

At the retrial, Dean claimed he never intended to trade on his office to benefit Adam. At one point, he even threw some blame on his son, saying it was “improper” for Adam to have accepted a $20,000 check for work he never did.

“Dean Skelos . . . refused to accept a single iota of responsibility for any of his actions,” prosecutors said.