Officers are aware of at least 40 women who have travelled to the Island in the past 12 months to work as escorts.
The sex workers, many of whom are Romanian, Latvian or Brazilian, book stays in local hotels or turn private, rented accommodation into 'pop-up brothels', the police have said.
They offer their services on the internet and charge up to £150 an hour.
There are currently 25 women advertising their services in Jersey on one website alone.
Dozens of so-called pop-up brothels have been disrupted in the UK in recent months.
Sex workers, or organised-crime gangs, book the accommodation for short periods to avoid detection.
Detective Chief Inspector Lee Turner, of the States police, said that the 40 women the force had made contact with were 'not the full picture'.
He added that he feared a 'significant proportion' were being forced into the sex trade by mainly eastern European organised-crime gangs working out of the UK.
Asked if there was any evidence to suggest that sex was being sold on the Island's streets, Det Chief Insp Turner said: 'We know we don't have a red-light district, but it is likely sex is being offered discreetly, perhaps in pubs. It would be wrong to say that it is not happening.'
In late 2014, following a number of intelligence tip-offs, the force launched Operation Phoenix, which focused on the trafficking of women into and around the Island to work in the sex trade against their will.
In December 2014, Romanian national Catalin Mihail Avram was banned from the Island for three years by the Magistrate's Court for running a brothel with two women out of a flat at Panama Apartments in Green Street. One of the women was his pregnant girlfriend.
Up to three more arrests have been made since the Avram prosecution in relation to women being sold for sex, but the cases were dropped due to a lack of evidence.
The officer added: 'It's difficult to give a definitive picture, but we have identified something in the region of 35 to 40 different working ladies travelling to Jersey over the past 12 months.
'A number of these are repeat visitors.
'A significant proportion of these ladies will be working for organised-crime groups and they are being forced or coerced into the sex trade. These 35 to 40 women are not the full picture either.'