A rise in cases has prompted the policy reversal.
Denmark is set to reintroduce its COVID health pass - two months since the Scandinavian nation stopped using it.
On Monday, for the fifth day in a row, the country reported more than 2,000 new COVID cases.
Prime Minister Mette Frederiksen said the reintroduction of the pass would be "harder for those who aren't vaccinated."
"That's how I think it should be," she said.
In Denmark, 85.9% of those over the age of 12 received two doses of vaccine.
According to the head of government, the increase in cases is due to a "small group that does not play by the rules".
"They are accountable to the whole of Danish society right now," she said, calling on those undecided to get vaccinated.
A bill to reintroduce the pass will be presented to parliament today (Tuesday, November 9).
Last weekend, health authorities warned of a risk of the country's hospitals being "overloaded" because of the "risk of Covid-19, the flu and other infectious diseases".
Denmark was a pioneer of the COVID health pass, which carries proof a person has been vaccinated against COVID-19. It abolished the pass on September 10, at a time when the number of new cases was four times lower than today's figures.
The move to reintroduce the pass for accessing indoor bars and restaurants is subject to parliamentary approval.