United were preparing to face Everton in a friendly at Old Trafford in front of an expected crowd of 55,000 and confirmed starts for captain Harry Maguire, Luke Shaw and Anthony Martial.
But the club added: "Unfortunately, Jesse Lingard is unavailable after testing positive for COVID-19. He is isolating in line with government and Premier League guidelines."
Lingard enjoyed an outstanding loan spell with West Ham last season, scoring nine goals in 16 Premier League appearances.
The England international netted on average once every 158 minutes, the 11th-best rate in the division among players with multiple goals.
Lingard, who also provided four assists last term, has returned to the first-team fold at United in pre-season.
He posted on his Twitter page on Saturday: "Really gutted to have tested positive after a good pre-season.
"Luckily I feel fine and will follow the guidelines and be back with the boys on pitch very soon! Thank you for your support."