The UK is bottom of a league table for child well-being across 21 industrial countries, charity Unicef has said.
The study looked at 40 indicators including poverty, relationships with parents, health and safety, behaviour, and children's own sense of well-being.
The Netherlands, Sweden, Denmark and Finland headed the list, with the UK in last place just behind the US.
The Children's Society described the findings as "shocking" and said the UK was failing children.
'Child potential'
The UK rated highly for education but was in the bottom third for all of the other categories.
A spokesman for the UK government said it had made progress on child well-being through a number of initiatives in areas such as poverty, pregnancy rates, teenage smoking, drinking and risky sexual behaviour.
Unicef - the United Nations' children's organisation - says the report, titled Child Poverty in Perspective: An Overview of Child Wellbeing in Rich Countries, is the first study of childhood across the world's industrialised nations.
Unicef UK executive director David Bull said all the countries had weaknesses that needed to be addressed.
"By comparing the performance of countries we see what is possible with a commitment to supporting every child to fulfil his or her full potential," he said.
The Children's Society has launched a website to coincide with the report,
www.mylife.uk.com, which allows children to answer a series of surveys about their lives.
Commenting on the Unicef report, the society's chief executive Bob Reitemeier said: "We simply cannot ignore these shocking findings.
"Unicef's report is a wake-up call to the fact that, despite being a rich country, the UK is failing children and young people in a number of crucial ways."
The Children's Commissioner for England, Professor Al Aynsley-Green, said he was not surprised by the report's findings.
"It's very much in line with what children and young people are telling me about their lives today, and I think the shocking conclusion is that as a nation we have been failing our children and young people."
'Failed generation'
Colette Marshall, UK director of Save the Children, said it was "shameful" to see the UK at the bottom of the table.
"This report shows clearly that despite the UK's wealth, we are failing to give children the best possible start in life," she said.
"The UK government is not investing enough in the wellbeing of children, especially to combat poverty and deprivation."
Shadow Chancellor George Osborne accused Chancellor Gordon Brown of having "failed this generation of children".
"After 10 years of his welfare and education policies, our children today have the lowest wellbeing in the developed world," said Mr Osborne.
REPORT FINDINGS
UK child poverty has doubled since 1979
Children living in homes earning less than half national average wage - 16%
Children rating their peers as "kind and helpful" - 43%
Families eating a meal together "several times" a week - 65%
Children who admit being drunk on two or more occasions - 30%
A government spokesman said it regarded the improvement of the life of British children as a matter of particular importance.
"Nobody can dispute that improving children's well-being is a real priority for this government," she said.
"We recognise that Unicef does vital work in this area. But in many cases the data used is several years old and does not reflect more recent improvements in the UK, such as the continuing fall in the teenage pregnancy rate or in the proportion of children living in workless households.
"We are working hard to improve all children's life chances and the report confirms that children's educational attainment at 15 in the UK compares well with many other EU countries."
CHILD WELL-BEING LEAGUE TABLE
1. Netherlands
2. Sweden
3. Denmark
4. Finland
5. Spain
6. Switzerland
7. Norway
8. Italy
9. Republic of Ireland
10. Belgium
11. Germany
12. Canada
13. Greece
14. Poland
15. Czech Republic
16. France
17. Portugal
18. Austria
19. Hungary
20. United States
21. United Kingdom
Source: Unicef
