Help the Aged claims that 53 per cent of Brits think the government treats elderly people like "second-class citizens".
A survey conducted by the charity as part of its bid to ban age discrimination also highlights that 81 per cent of respondents think such inequality is already illegal, despite the fact that it is only banned in relation to the workplace.
Paul Cann, director of policy and external relations at Help the Aged, says: "Ageism is the only 'ism' that is still perfectly legal. It's not surprising that the public think older people are treated as second class citizens."
He adds that such prejudices can sometimes mean the difference between life and death.
Help the Aged is calling on the government for legislation against age discrimination regarding provision of goods and services such as health care and has warned that failure to do so could result in Labour losing the "grey vote".
The government recently launched a campaign for elderly dignity, with Sir Michael Parkinson as an ambassador.
Health secretary Alan Johnson will be joined by the former talk show host as he visits healthcare providers around the UK to discuss elderly care.