Matuidi is the second Juve to be diagnosed with the virus after Daniele Rugani was confirmed as its first case last week.
Like Rugani, Matuidi's test has come back positive despite the player not developing any symptoms; however, he had already been in isolation since his team-mate's diagnosis.
A statement released by Juve read: "Blaise Matuidi has undergone medical tests that have revealed his positivity to the coronavirus-COVID-19.
"The player, as of Wednesday March 11, has been in voluntary home isolation. He will continue to be monitored and will follow the same regime. He is well and is asymptomatic."
Football in Italy is suspended until April 3 due to the pandemic, but Italian Football Federation (FIGC) president Gabriele Gravina has already suggested it is not realistic to expect action to resume at the start of next month.
EURO 2020 was due to start in Italy's capital Rome on 12 June, but the tournament's postponement until June 2021 was confirmed by UEFA.
No country outside China has been more heavily affected by the virus.
COVID-19 was declared pandemic last week and has affected 196,000 people worldwide, with just under 32,000 cases recorded in Italy, where 2,503 deaths have occurred.