The angry carers gathered in the city centre to voice their opposition to the proposed changes to personalised services based on individuals' needs to meet new UK Government rules.
Included in these plans are the closure of day care centres in Summerston, Berryknowes in Cardonald, and Hinshaw Street, Maryhill.
About 400 people each day attend the city's seven council-run centres for people with learning disabilities.
Under the plan, about 200 people with the most complex disabilities would continue to be supported in council-run day centres at Riddrie, Calton, The Wedge in Pollok, and Southbrae, Jordanhill.
The plans will be considered at the Health and Social Care Policy Committee on March 6.
About 520 families will be affected if the plans are approved and the centres are shut.
Tommy Gorman has campaigned against the closures after what he calls "a severe lack of consultation" with people who use the centres.
His daughter Patsy, 21, has learning disabilities and uses the centre in Summerston.
He said: "Patsy has lots of friends in the day centre, and what the council proposes will mean she and many day centre users will face isolation.
"Being stuck in front of daytime television is the worst option possible for anybody, particularly a person with a learning disability.
"The families that use the centres regard them as safe and secure hubs, where people with learning disabilities can meet their friends.
"And the highly trained staff at the centres are very skilled at assisting people with disabilities."
Mr Gorman also fears there will be insufficient provision of services by the council, should the closures go ahead.
He added: "The council's vague promise of assisting the people in the community is something we are concerned about.
"Day centres have closed before and people who have left these are still looking for the facilities Glasgow City Council said were available."
Protesters say the loss of the three centres will also impact people using all of the existing seven day centres.
Eileen McSherry's sister Karin, 50, has Down's syndrome and uses the Carlton day centre.
Even though that centre is not set for closure, Ms McSherry says Karin will be unable to keep using the services – as she has done for 30 years – because she is not considered to have "complex needs".
Ms McSherry, who is her sister's unpaid carer, said: "Karin has a big circle of friends and they are going to take all that away from her and isolate her.
"We only get 30 hours a week, we're not asking for much. The council is assuming carers will be able to pick up the downtime – that is arrogance.
"The people it will affect can't cope with all these changes in their life. They need to be treated sensitively, but the council is treating them like cattle."
Steven Alexander's sister, Linda, 30, also goes to the Carlton centre and will suffer the same problem as Karin.
Mr Alexander, 47, said: "I am a full-time, unpaid carer for my sister, who has Down's syndrome, congenital heart disease and health issues.
"If this goes ahead, I do not think I will be able to care for her. Unless we arrange all our own support or something like that, it is just going to be more of my time. It will be a big strain."
Glasgow's SNP councillors added their support to the families, who want the process halted.
Susan Aitken, councillor for Langside, said: "The Labour administration in Glasgow really does not seem to understand what consultation means.
"If it can accept it did the wrong thing on plans to redesign George Square, surely it can do the same when it comes to services for vulnerable people?
"It is not too late for the council to follow the advice of its own Carers' Champion and put a moratorium on talk of closures and hold proper discussions."
Mr Kerr, said: "The Scottish Government's plans for self-directed support means the way social care is delivered is going to change. Tackling this issue now and planning carefully for the future is the right thing to do.
"I understand we are proposing a big change and people can feel nervous.
"The vast majority of service users who have already moved on from day centres make it clear they do not want to go back.
"With the right support in place, they have relished having more control over their lives."