The suspects, aged between 30 and 75, were arrested in raids over the past two weeks.
Inspector Keung Pei-ying of the Kwun Tong district special duties unit said on Friday the group comprised 17 Hongkongers and 9 mainlanders holding two-way exit permits, a travel document used to enter the city.
Police charged the suspects over allowing their premises to be used as vice establishments and breaching their conditions of stay.
The force and the Immigration Department conducted two operations between May 20 and 30, with a focus on Kwun Tong district in East Kowloon after police earlier found evidence of sex workers operating in the area.
An investigation found the syndicate imported women from the mainland as sex workers to offer services in subdivided flats.
“Police have sent warning letters to those flat owners numerous times to ask them not to rent out their flats to the syndicate, but the owners neglected them,” Keung said.
The lack of follow-up prompted police to start the operations by targeting the flat owners, she added.
“We urge flat owners not to lease their flats to prostitution syndicates, as it might result in imprisonment,” Keung said.
In a separate case last month, police arrested 51 people in connection with bringing in sex workers from the mainland and Thailand to work in Yau Ma Tei.
In Hong Kong, operating as a sex worker is legal but it is against the law to solicit clients, run a brothel of two or more people, live off the earnings of a sex worker or control a woman for vice purposes.
Anyone who keeps or manages a premises as a vice establishment also faces up to 10 years in jail.