Roy Marshall, 52, accompanied Kevin Lester to the bank to help him withdraw money from a cash machine, Sheffield Crown Court heard.
But instead of handing over all the notes to Mr Lester he would pocket some of the cash for himself, stealing £2,820 over a three-year period.
The court heard as well as being registered blind, 55-year-old Mr Lester suffered from mild learning difficulties, arthritis and needed one-to-one care for 24 hours a day.
Carl Fitch, prosecuting, said Mr Lester needed someone to trust and Marshall, of York Road, Eastwood, Rotherham, was his carer for 12 years.
Marshall helped the blind man with his daily living needs and also went with him to the bank where he usually took out £200.
The carer, who was employed by care company Direct Health, would hand over the cash and obtain a receipt which he put into a log he kept at home.
Marshall was arrested last October after his employers checked the logs at his home against Mr Lester’s bank statements and found £2,820 was missing.
Mr Fitch said: “He fully accepted taking money out of his account, giving some to Mr Lester and pocketing the rest himself.”
“He said he had a drink problem and that was why he was taking the money.”
Marshall admitted three offences of fraud by abuse of position between January 8, 2009 and May 15, 2012.
Michael Upson, defending, said for nine years Marshall had been a model carer, teaching the blind man crafts, gardening and fishing and he even went on holiday with him.
Judge Alan Goldsack told Marshall he had systematically robbed Mr Lester of small amounts of cash over a long period.
He said: “You were employed to look after this man and whilst you did that without complaint it doesn’t lessen the seriousness of what you have been doing over the last three years.”