The luxury car group said 24 employees at the factory in Solihull have tested positive for Covid-19.
JLR, which employs about 7,000 people at the site on Lode Lane, says that all those affected were now self-isolating.
A deep clean has been carried out at the factory.
Through contact tracing and working in conjunction with Public Health England and Solihull Council, JLR says it has identified anyone who has been in close contact with those individuals at work and they are also self-isolating.
There are also currently two workers self-isolating after testing positive for coronavirus at JLR's engine manufacturing centre at the i54 to the north of Wolverhampton.
The two cases are separate.
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The company said it has had isolated cases of Covid-19 across its operation, with stringent measures at all its UK factories to ensure social distancing and prevent the spread of coronavirus - including temperature checks with thermal cameras.
All production lines, engineering facilities, office areas and communal spaces have been reviewed as the company gradually returns to manufacturing.
JLR says it continues to monitor the Covid-19 situation and follow the guidance of all relevant authorities.
Corporate affairs manager Lisa Palmer said that all UK sites were now operating and less than 5,000 employees were still on furlough.
The group is currently evaluating the measures announced on Thursday by Chancellor Rishi Sunak to see whether they can be utilised to further protect jobs.