Melanie Harris, 44, emptied the bank account of 65-year-old Ted Carter, who had cerebral palsy, and used it for shopping trips and family presents.
Harris, from Barnstaple, had denied one count of fraud but was jailed for two-and-a-half years for the thefts which took place between 2011 and 2013.
The Recorder said she had abused "a highly vulnerable housebound man".
Harris was responsible for looking after Mr Carter and his wife who used a wheelchair, at their bungalow in Wikley Close, Barnstaple, as a team leader with the private care provider, Cygnet Care.
Police described her house in Fremington as "looking like a show home", after Harris used the couple's debit card on a series of shopping trips, Exeter Crown Court heard last year.
Harris, who hid Mr Carter's bank statements to cover up the thefts, was caught after another carer noticed Mr Carter's money had been used for a baby shower.
Recorder Philip Mott said: "He trusted you with his card, PIN and passbook and trusted you as a co-signatory. As a result, you had complete control over his accounts."
The recorder said Harris was motivated by "family expenses", and cited the probation report which spoke of her "greed and a desire to fund a lavish lifestyle".
A care worker has been jailed for stealing £75,000 from a patient to spend on a "lavish lifestyle".