Bang Rak police deputy inspector Pol Captain Thanapat Suwannak said the body of the foreign tourist, whose name was later identified as Maceiras Rijo Vera, was found entangled in a barbed-wire fence at the base of the hotel on Maha Nakhon Road in Maha Preuktharam sub-district at 8am.
Police determined that she was sharing a hotel room on the third floor with her elder sister.
They suspect she committed suicide.
A CCTV footage reportedly showed that she went to the open deck to perform a yoga at around 5am.
The body was sent to the Police General Hospital for autopsy.
The Portuguese embassy was asked to co-ordinate for the transport of her body back to home country for religious rites.