Figures gathered from children's services and health trusts show 31 deaths were suicides, including six in under-18s.
More than 50 young asylum seekers in the UK have died in the past decade, the majority by suicide, according to data compiled for the first time.
Of 54 deaths of children and young people who claimed asylum between 2015 and 2024 in the care system, 31 were due to suicide, with seven homicides and eight fatal accidents. Only six deaths were due to health issues with two causes of death unknown, and 44 of the 54 have occurred since 2020.
The information was collected by Da'aro Youth Project, which supports young asylum seekers.
All local authority children's services departments in England, Scotland and Wales and all health and social care trusts in Northern Ireland were approached for data, using freedom of information requests. The Home Office and Department for Education refused to provide this data.
Since 2024 the Office of the Information Commissioner has issued five separate decision notices finding that Home Office wrongly withheld information about asylum seeker deaths. The Home Office is appealing against four of these decisions.
The data obtained from local authorities is likely to be incomplete because the Home Office often disputes the ages given by young asylum seekers, so not all end up in the care system. In one recent case, a child, initially deemed to be an adult by the Home Office, was charged with endangering others on a small boat crossing.
The new report was authored by Benny Hunter, the co-founder of Da'aro Youth Project. The data shows that 2024 was the highest single year for deaths, with seven suicides and seven other deaths.
Amir Safi, from Afghanistan, who said he was 16, died in 2024 after becoming "very quiet and withdrawn" when he was ruled an adult.
When broken down into age categories, six suicides involved children aged 17 or under, 16 were of young people aged 18 to 20 and nine were of 20- to 24-year-olds.
The majority of deaths occurred in the past five years. However, between November 2017 and February 2019 there were four suicides of Eritrean teenagers who knew each other - Alexander Tekle, Osman Ahmed Nur, Mulubrhane Medhane Kfleyosus and Filmon Yemane.
The report has been sent to various ministers including the education secretary, Bridget Phillipson, and the immigration minister, Alex Norris, with an accompanying letter that says: "We are deeply concerned about the lack of transparency from the government about these deaths. The Department for Education and Home Office have both withheld requested information."
It adds: "We believe that all children and young people matter, regardless of their immigration status, national origin or ethnicity."
The report calls for death data for this group to be published, for a national review of these deaths to be undertaken and for a new safeguarding strategy to be implemented for this group of young people.
Sarah Robson, director of the Da'aro Youth Project, said: This is the first time this data has ever been compiled - and we find it to be very shocking. Unaccompanied young people, who have been forced to flee their homes and have come to the UK to find safety and sanctuary, are dying by suicide in great numbers.
"These young people have been mistreated repeatedly by governments - with children treated as adults by the Home Office - and an asylum system that prioritises deterrence over sanctuary."
The Home Office and DfE have been approached for comment.