In a report launched today, the Carers Trust found only 56% of carers were given information on managing behavioural problems, compared to 68% across the UK.
Half of carers have had difficulties getting a dementia diagnosis, compared to 52% across the UK and only 51% of carers said they had had an opportunity to talk about their own needs.
Charities leaders described the findings as "alarmingly bad". However, there were two areas where Scotland fared slightly better than the rest of the UK.
Of 350 carers surveyed across the UK, 61% said it had adversely affected their ability to work, compared to 82% across the UK and 91% of Scottish carers were given information on legal issues such as Power of Attorney and wills compared to 55% across the UK.
The report found there were a number of critical points along a carer's journey where they would most value information and support.
These include when dementia is diagnosed, when the carer has to cope with behavioural problems or needs a break from caring.
Ann Marie Craig, 43 from Castlemilk, has cared for her 77-year-old uncle John since 2006. He suffers from a number of health issues including vascular dementia, stroke, severe deafness and blindness.
He lives in the East End of the city and Ann Marie travels there from Castlemilk every day to support him.
Ann Marie has five children aged four to 21, and said the whole family had been affected by her caring responsibilities.
It was only after going to Glasgow South East Carers Centre that Ann Marie was able to access support with care for her uncle, including statutory home care and information about Power of Attorney.
She said: "Having young children from the point of diagnosis, my job would have been made 100% easier if there had been better access to childcare and nursery places.
"My four-year-old has lost an entire year of nursery.
"John cared for me and my brother after my parents passed away, so I wanted to care for him.
"Dementia is a terrible, terrible thing. But the other side is the carer, we need support too. It's a very emotional thing, caring for someone.
"There was a long gap between the discharge from hospital this year and an assessment for a care home.
"The summer has been really, really difficult. We've now found him a suitable home which is a big weight off my mind."
Esimates suggest there are around 71,000 people with dementia in Scotland.
There are 650,000 carers in Scotland, although there are thousands more hidden carers who are not being supported by services.
Three out of five of us will become carers at some stage in our lives and one in 10 of us is already fulfilling some sort of caring role.
The value of care provided by carers in Scotland is £10,347,400,000 a year.
Florence Burke, director for Scotland, Carers Trust, said: "It is clear from this report, and from anecdotal evidence from carers' centres across Scotland, that carers of people with dementia are not getting the support that they need.
"Although the findings show that there are some instances where Scotland is performing comparatively well, the overall picture is alarmingly bad.
"The evidence from this report has highlighted the fact that all professionals will need to check that carers have the information and advice appropriate for the challenges they are currently experiencing."