The former 'That '70s Show' co-stars have been staying in the Italian capital while Kunis, 29, films 'The Third Man' with Liam Neeson and James Franco.
On Friday they stepped out in the Testaccio district to have an intimate meal at Checchino, reported Us magazine.
Sporting a grey hat, pale blue sweater, grey pants, and a navy peacoat, the 'Two and a Half Men' actor, 34, led his love of six months through the stone streets of the city as they made their way to the restaurant.
The 'Black Swan' actress kept warm in black pants, a plaid shirt, printed scarf, and black cloche hat.
The jet-setting couple, who've been spotted everywhere from Los Angeles to Australia since hooking up in April, seem to have taken quite nicely to Rome.
Last week, they enjoyed a romantic after-dinner stroll to take in the sights. And before Thanksgiving, they joined Kunis' Third Man co-stars and director Paul Haggis for a three-course feast at Antica Pesa.
"They're really serious," an insider said of Kunis and Kutcher, who split from wife Demi Moore in November 2011.