The bears, including Malayan sun bears and Asiatic black bears, were owned by 62-year-old Suphan Thammasatsit.
Mr Suphan had intended to open a zoo in Ban Na district, but scrapped the plan several years ago.
In 2003, Mr Suphan reported to the Department of National Parks, Wildlife and Plant Conservation that he owned a number of wild animals. He also asked the authorities to take care of the bears, but the department said they did not have the budget to relocate and look after the animals at that time.
Somsak Dokmai, director of the wildlife preservation division in Prachin Buri province, yesterday led a team of 30 officials and veterinarians to move the bears to a wildlife rehabilitation centre in Chon Buri province.
Mr Somsak said the authorities did not seize the bears earlier because they could not afford to and the wildlife rehabilitation centres were overcrowded.
But now, the department had sufficient funds and vacant space to take care of the bears.