The government faces accusations of being "fundamentally dishonest" about its policies towards disabled people.
TUC general secretary Brendan Barber will tell a conference on Wednesday that disabled workers are being hit more than other groups by the coalition's austerity cuts.
He will tell the TUC's Disabled Workers Conference: "No group of people is more affected by the government's savage, ideological austerity than disabled workers. It's no exaggeration to say that when it comes to disability, there is a fundamental dishonesty about government policy.
"The coalition is keen to promote the language of fairness and is keen to stress the opportunities available to disabled people, but the truth could not be more different. Nowhere is the dichotomy between rhetoric and reality starker than when it comes to benefits - a lifeline for so many disabled people.
"As the right-wing press peddles its demeaning myths about workshy scroungers, the government is slashing £17 billion from the welfare budget. It is the poorest and most disadvantaged people who are suffering the consequences."
Mr Barber will say that the government's welfare reforms are causing "immense damage".
Disabled workers facing redundancy because of the closure of Remploy factories staged a protest outside a charity on Tuesday.
Dozens of workers pitched tents outside the London offices of Disability Rights UK as part of their protest against plans to close Remploy factories across the UK with the loss of jobs.
Unions have accused the government of planning to close all 54 Remploy sites with the loss of 2,800 disabled workers' jobs.
A Department for Work and Pensions spokesman said: "This government is absolutely committed to supporting disabled people and continues to spend over £40bn a year on disabled people and their services. However too many disabled people have been systematically failed by the current benefits system.
"Our welfare reforms will simplify the system to make sure that the billions we spend on disability benefits offers more targeted support for those who need it most.
"And that we use the protected £320m disability employment budget more effectively to get thousands more disabled people in mainstream jobs instead of segregated factories."