Norwegian King Harald V and his wife, Queen Sonja, were vaccinated against Covid-19 on Wednesday, the palace said.
Both are aged 83 and therefore considered at risk from the respiratory disease.
They were due to receive their next dose in about three weeks time, the palace statement read.
The king and queen self-isolated from time to time last year, including in November, after a palace employee tested positive for the virus.
The king and queen also self-isolated in March - in line with government guidelines - after conducting a state visit to Jordan.
The couple spent part of the Christmas holidays with their children and grandchildren.
Princess also vaccinated
The palace said the king's 88-year-old sister, Princess Astrid, was also vaccinated on Wednesday, public broadcaster NRK reported.
Norway began its vaccination campaign on December 27.
The Scandinavian country of about 5.3 million has in total recorded 509 coronavirus-related deaths and about 56,600 infections.