Guendouzi is currently not displaying any symptoms but will undergo a 10-day period of self-isolation.
Guendouzi tested positive after returning to Germany following his exertions with the France u-21 side during the international break.
The 21-year-old captained France in Euro u-21 qualifying wins over Liechtenstein and Slovakia.
“Matteo Guendouzi has tested positive for Covid-19 after returning from international duty,” read an official statement from Hertha Berlin.
“There has been no contact with any Hertha players or staff. He is symptom-free and feeling well, but will now self-isolate for 10 days.”
Guendouzi joined Hertha Berlin on a season-long loan deal from Arsenal on transfer deadline day after falling down the pecking order at the Emirates Stadium.
His last game for Arsenal came on June 20 against Brighton in the Premier League when he was involved in an angry confrontation with Neal Maupay.
Guendouzi is yet to make his debut for Hertha Berlin and will miss their return to Bundesliga action against Stuttgart this weekend.
Bruno Labadia’s men are 13th on the table, with one win and two defeats from their opening three games.