Kristina Novitskaya, 30, was discovered at her home in the Bodrum resort on the Aegean coast on Saturday. She had died a few days earlier.
The front door was locked with the key inside, the windows were also secured from the inside and there was no trace of any struggle.
Local police say the main line inquiry is suicide, but her friends say that 'life-loving' and 'cheerful' Ms Novitskaya would not have ended her own life.
However, they added that she was 'secretive' about her private life in Turkey, where she lived and worked as an interpreter and dance instructor.
'We do not believe that she committed suicide,' a friend told Obozrevatel media in Kyiv.
Reports say Turkish police believe she had become depressed at a lack of work due to the pandemic, yet the precise cause of death has not been revealed.
After her family, friends and neighbours could not reach her, they alerted police. Her body was found in a sitting position on a chair in the middle of the room.
She was handcuffed, and a plastic bag was on her head, say reports.
Ropes, charcoal, and a scarf were also found at the scene but no cause of death has been announced so far.
The corpse has been sent to the Institute of Forensic Medicine for an autopsy.
The door was locked from inside, and a key was inside the keyhole, say reports citing Turkish police.
Windows were locked and there was no trace of a fight. A video shows the exterior of her home, and the security guards' office at the complex.
Ms Novitskaya was a graduate of Kiev National Linguistic University where she studied oriental languages.
She spoke Turkish fluently and worked as a professional interpreter.
'She was an incredibly kind, open-hearted, sweet person who would never get into a conflict and always helped others,' said a friend from her student days.
'She was quite secretive about her private life. Everyone who knew Kristina is deeply shocked. We do not believe that she committed suicide.'
Another friend said: 'True she didn't post about her love life on social media, but she was always so open, so full of life and happy.'
The friends dismissed as 'strange' the reports that she had become depressed, solitary and suicidal over the pandemic.
They hinted at a VIP associate in Turkey but gave no details.
'This is a strange version indeed,' said one friend. 'Kristina had family, and her mother is in Kiev. There was always another route to take which was to return home. Turkey had quite a spell of lively times when tourists returned in summer, Kristina would have found a job.
'I don't believe in these versions. I think they are trying to cover up for someone important.'
Turkish police reported that CCTV cameras showed no visits since a food delivery on 31 December. Her body was found on Saturday.
Her mother was travelling to Turkey from Kyiv.