De Ligt follows team-mates Alex Sandro and Juan Cuadrado in missing this weekend's league match against Sassuolo as well as next Monday's (AEDT) trip to Inter Milan and 21 January's (AEDT) Italian Super Cup final with Napoli because of the illness.
"Juventus Football Club announces that, during the checks provided for by the protocol in force, Matthijs De Ligt has emerged positive with Covid 19," a Juve statement read.
"The player has already been placed in solitary confinement."
According to local reports Andrea Pirlo's squad will undergo tests to discover the presence of a virus cluster.
In October, Juve's Cristiano Ronaldo missed almost three weeks of games after contracting the illness and in March the club's former defender Daniele Rugani was the Italian top flight's first player to test positive for the virus. Paulo Dybala also had the virus in 2020.