The man was helping the woman at her home near Stockholm and had the key to her apartment, reported Expressen.
The woman said in testimony that the man masturbated in front of her and later raped her. Afterwards, she called relatives, but said she had a tough time describing what had happened.
She was taken to the hospital for treatment.
The man has admitted to the rape and DNA evidence was found by police. The man said a strange power forced him to vaginally rape the old woman.