Crown Prince Vajiralongkorn is expected to succeed King Bhumibol
There has been no official announcement of a divorce, but their separation is being seen as inevitable.
The princess's uncle, a police general, was arrested over accusations of amassing vast wealth through smuggling and gambling rackets.
Four of her siblings and two other relatives have also been held.
Srirasmi would have been expected to become queen when the crown prince succeeded his father.
This is not the first time a wife of the crown prince has been brought down in this very public way; his second wife was also discredited, then forced into exile 18 years ago.
The world's longest-reigning monarch, King Bhumibol, a widely revered and unifying figure, has been on the throne in Thailand since 1946.
The pivotal position of the monarchy in Thailand's political order makes the succession an extremely sensitive issue.
Many aspects still cannot be reported from inside the country.
The strict lese majeste law criminalises any critical comment about the monarchy.