The 10-year-old girl escaped her torturer by picking the locks on the chains around her feet and is being treated in hospital for burn marks on both hands, bruises on her face, swollen wrists and fractured ribs.
Shortly after she was admitted, police detained a relative with whom she had been living in the southern state of Johor, the New Straits Times reported.
Police said the girl, who has been in the care of the suspect since her father died, was believed to have been subjected to daily torture, supposedly to rid her of bad luck.
The suspect is believed to have beaten, burnt and starved her for about a month, after a medium said the girl was an unlucky omen, the report said.
Police have remanded the suspect for investigations, pending the victim's medical report.
In June, a Malaysian court sentenced a man to death for causing the death of a 3-year-old girl during an exorcism ritual gone wrong.