ASHTON KUTCHER can’t get DEMI MOORE out of his mind!

The 33-year-old actor turned heads in Berlin when he stepped out with a dead ringer for a young version of his estranged wife.

Kutcher – who split from 49-year-old Demi in November – attended a private party in the German capital with the brunette.

The hunky star, whose marriage fell apart following allegations he slept with a 23-year-old party girl in San Diego three months ago, spied the Demi look-alike around 1 a.m. and made his move.

“They sat by an open window chatting and appeared very flirty as they drank red wine and smoked one cigarette after another,” an onlooker told The ENQUIRER.

“Ioverheard them talking about past relationships. He was very open and seemed to be regretful about hurting Demi.

“But at the same time, he was obviously trying to charm the girl.

“After a short while, Ashton spotted three other girls trying to get into the party. He asked them to join him and the brunette.”

The evening ended on a high note for Ashton, who was later spotted arriving at an apartment with the Demi clone.

Ashton was in Germany on business, but an observer said: “He certainly was enjoying every-thing Berlin nightlife has to offer, including the beautiful women. It’s a wonder he got any work done!”