The car was later found stuck at the Wangaloa Domain - about 6km away - burnt out so it could not be returned to its owner.
"It is disturbing that the vehicle was stolen from a vulnerable person leaving him without any independent mobility," said Senior Sergeant Cynthia Fairley.
"It was bad enough to target a vulnerable person, but thieves went on to burn it out so it could not be returned to the owner.
"This theft will have a huge impact on this victim's life."
Police are interested in hearing from anyone who may have seen the vehicle driving around the Clutha District.
If you have any information, please contact your local police station, or anonymously via CrimeStoppers on 0800 555 111.