Talk about the great unwashed!

Kurt Cobain’s grubby, cigarette-burned cardigan just sold for an eye-popping $334,000 — even though it has not been washed since the rocker’s death.

The tatty green cardigan became an iconic part of the late Nirvana frontman’s image when he wore it for the band’s “Unplugged” special on MTV in 1993.

Cobain’s widow, Courtney Love, then gave the sweater — unwashed and clearly marked with cigarette stains and a burn hole — to a nanny and personal assistant after the grunge legend killed himself in 1994, according to Julien’s Auctions.

It was bought for $137,500 four years ago and was expected to make $200,000 to $300,000 at the auction over Friday and Saturday.

Instead, it went for $334,000 — more than double what the seller paid for it and the most expensive sweater auction of all time, according to Bloomberg. The winning bidder cashed in on the sweater over the phone and wishes to remain anonymous, Bloomberg said.

It sold for almost as much as the rocker’s custom-made left-handed Fender Mustang guitar, which at $340,000 got less than the $400,00 predicted.

“This cardigan, it’s the holy grail of any article of clothing that he ever wore,” the auction house’s CEO, Darren Julien, told AFP.

“Kurt created the grunge look; he didn’t wear show clothes.”

Cobain died by suicide at age 27, about six months after taping “Unplugged.”

Earlier this year, the sweater Cobain wore during his last photoshoot with Nirvana sold for $75,000, more than double Julien’s estimate.

With Post wires