Philip Chawner, 53, and his 57-year-old wife Audrey weigh 24st. Their daughter Emma, 19, weighs 17st, while her older sister Samantha, 21, weighs 18st.
The family from Blackburn claim £22,508 a year in benefits, equivalent to the take-home pay from a £30,000 salary.
The Chawners, haven't worked in 11 years, claim their weight is a hereditary condition and the money they receive is insufficient to live on.
Mr Chawner said: "What we get barely covers the bills and puts food on the table. It's not our fault we can't work. We deserve more."
The family claim to spend £50 a week on food and consume 3,000 calories each a day. The recommended maximum intake is 2,000 for women and 2,500 for men.
"We have cereal for breakfast, bacon butties for lunch and microwave pies with mashed potato or chips for dinner," Mrs Chawner told Closer magazine.
"All that healthy food, like fruit and veg, is too expensive. We're fat because it's in our genes. Our whole family is overweight," she added.
Each week, Mr and Mrs Chawner, who have been married for 23 years, receive £177 in income support and incapacity benefit. Mrs Chawner is paid an extra £330-a-month disability allowance for epilepsy and asthma, both a result of being overweight.
Mr Chawner gets £71 a month after developing Type 2 diabetes because of his size. He was on a waiting list for a gastric band last year, but a heart condition made the operation unsuitable. Their daughter Samantha receives £84 in Jobseekers' Allowance each fortnight while Emma, who is training to be a hairdresser, gets £58 every two weeks under a hardship fund for low-income students.
Emma, said: "I'm a student and don't have time to exercise" she said "We all want to lose weight to stop the abuse we get in the street, but we don't know how."
