People arriving in Scotland from Luxembourg will have to self-isolate for 14 days as restrictions are reimposed in the European country.
A rise in Covid-19 cases means Luxembourg has been taken off the list of countries exempt from quarantine, the Scottish Government said.
It follows a similar decision about Spain on July 25.
The measures will come into force from midnight on Friday, having been announced only hours before.
Justice Secretary Humza Yousaf said: “This decision is based on the latest available data from the Joint Biosecurity Centre and it gives another clear indication that the virus is active and still spreading.
“We have always maintained that we are closely monitoring the pandemic situation in all countries and we will impose quarantine requirements as necessary in a bid to protect the public.
“This virus is showing a resurgence in areas and it should not be forgotten how deadly it remains.
“Our priority to is suppress the virus, prevent it from being transmitted and protecting public health.”