Having starred against England, the midfielder will now miss the Croatia game as he self-isolates for ten days.
It is reported that no close contacts have been identified and the rest of the Scotland squad will train as normal today ahead of Tuesday night’s fixture.
The statement said: "The Scottish FA can confirm that a member of the Scotland National Team playing squad, Billy Gilmour, has tested positive for COVID-19.
“Having liaised with Public Health England since the positive test was recorded, Billy will now self-isolate for 10 days and therefore miss tomorrow’s UEFA EURO 2020 Group D match against Croatia at Hampden.”
Gilmour was awarded the man of the match for his performance in the 0-0 draw with England and drew comparisons to N’Golo Kante by the Netherlands wing-back Patrick van Aanholt, while his former Chelsea boss Frank Lampard labelled him a “top, top player”.
It was the 20-year-old’s first start for his country and he was expected to line-up against Croatia in Tuesday’s crucial Group D fixture which will determine whether Scotland will qualify.
A win could, depending on results elsewhere, ensure qualification for Scotland. Gilmour would miss a potential last-16 clash which could be against the Netherlands or possibly Spain.
If he was to play in the tournament again it would mean Scotland reaching the quarter-finals.
It is the second time a Scotland player has tested positive for Covid-19 since the squad was announced. John Fleck had to self-isolate prior to Euro 2020 starting.