The detained men deny the rape accusation but media reports say one of them has said that consensual sex took place.
The alleged victim, a 34-year-old Canadian woman, says she met four officers at an Irish pub on Tuesday evening.
A fourth police officer has been released with no charges.
After a night of drinking, she says she went with them to see the police station and she claims to have been assaulted there.
The officers, aged 35 to 45, denied sexual relations took place.
DNA tests were underway on Saturday.
Court sources say the three officers held in custody were to face possible sexual assault charges on Saturday afternoon.
The officers are all members of a well known criminal investigation division of the French police with its headquarters on Paris's central Ile de la Cité.