Capability Scotland estimates 50,000 people will lose benefit and the Scottish Government believes around 30,000 will have their payments decreased and another 27,000 will not qualify at all.
Pam Duncan, has arthritis and uses a wheelchair.She works as a policy officer for Independent Living in Scotland with disabled people's charity Inclusion Scotland in Glasgow.
She receives higher rate DLA which pays for a car under the Motability scheme.
Ms Duncan could be affected by changes in allowances which range from Disability Living allowance to Personal Independence Payments, and new rules on how far someone can walk before they qualify for the higher rate, and then qualifies a person for mobility allowance.
She said: "It is essential for me. If I didn't get higher rate mobility allowance I wouldn't have a car and couldn't get around or to my work.
"I can't normally use buses so I need to use the car or use taxis when I am taking the powered chair as it doesn't fit in the car.Without it I would be stuck . I wouldn't be able to work.
"I wouldn't even have a job as the DLA allowed me to get about when I was a student and do voluntary work which gave me the experience to help get a job.
"Other students worked in bars and clubs but I couldn't do that and needed the allowance to be mobile to get to my volunteering."
Ms Duncan said the changes would be counter productive as the savings will be wiped out by an increase in costs in other parts of the public services costing the NHS or local council.
She added: "If they took it away I would pop up elsewhere in the system. I would need more health care and more supported care. I wouldn't work so I would need benefit from the department of Work and Pensions so it might save on one benefit would cost the public purse even more if I had it removed.
"I don't yet know if I will qualify for the higher rate under the new rules.
"I can walk a little and could possibly walk the distance on a good day with someone at my side ready to catch me if I fall."
The bedroom tax also affects disabled people but for many the room is used to store essential equipment for mobility.
Alan Dick, from Cardonald, has Cerebral Palsy and is worried he will be hit by the 'bedroom tax' .
He rents a two bedroom flat from GHA and uses the second bedroom to store his wheelchair and a hoist.
He said: "My bedroom is not lying empty, I need it for equipment I can't do without and for occasional sleepovers from carers. I get support seven days a week, but not 24 hours a day and that could be cut as well."
Alan's rent is more than £200 a month and if he had a cut of 14% for one 'spare' room he would have to find around £30 a month.
He added: "If I get my housing benefit cut and have to pay extra, I will have to cut back on something else and the only thing I could try and reduce is on food or heating.
"Even then as a wheelchair user there are certain foods I need to eat and some I shouldn't so the choice is limited."
Campaigners argue disabled people will be hit with a double whammy of reduced income and reduced mobility cutting them off from their families, communities and opportunities.
Richard Hamer, Director of External Affairs at Capability Scotland said: 'It's no surprise that at Capability Scotland we're hearing from disabled people, and their families and friends, of their fear about what welfare reform will mean to them. Probably biggest among their fears is the introduction of Personal Independence Payments from June.
"As soon as the new benefit is introduced disabled people in real need will start to lose money. Whilst the benefit rates remain the same as for Disability Living Allowance, the benefit it replaces, far fewer will get it.
"By May 2018 Capability Scotland's analysis of the DWP's figures shows nearly 50,000 disabled Scots, or 1 in 5 of the total current claimants, will have lost the benefit. 40% of those that continue to receive benefit will receive less.
"Those who lose, or get reduce, benefit also face losing other benefits and entitlements, leaving them even worse off.
"They may lose their adapted Motability car, their Blue Badge, free or reduced cost travel on public transport, or reduced cost or free access to local authority facilities."
TENS of thousands of disabled Scots will lose benefit payments, stopping them from working and preventing them from being mobile, charities warned today.
In a series of articles the Evening Times has looked at the impact of the reforms from Universal Credit to the 'Bedroom Tax' and the impact on families in the city.
Today Political Correspondent STEWART PATERSON speaks exclusively to two people who are worried the Government's welfare changes will have a dramatic impact on their lives.