Only two-thirds of children in Britain live with both parents, leaving the country with one of the highest rates of family breakdown in the Western world.
According to an Organisation for Economic Co-operation and Development (OECD) report, 68.9% of children live in the same household as their parents at the age of 14, well below the Western average of 84%.
Only Belgium, Latvia and Estonia fare worse than Britain in the list of countries where both a child's father and mother live together.
Social-justice campaigners say the figures reveal an "appalling epidemic of family breakdown".
The UK stands in contrast to most other west European countries with Finland on top at 95.2%, Germany at 82%, Italy at 92.1%, Spain at 91.5% and France at 79.5%. The US also had a higher number of children living with both parents, at 70.7%.
The figures, which relate to 2007, the most recent comparable period, come on the back of Scottish research about children affected by separation. Growing Up in Scotland (GUS) is an ongoing study launched in 2005 to chart the experiences of 14,000 children and their families.
In results released last year, it found that one in 10 children in Scotland sees their parents split up by the time they are five. The children are affected not just by the separation itself, but by its impact on their mother, according to researchers.
It showed parents appear most likely to separate in the first two years after a child is born, and points out that separation can leave the mother poorer, or suffering poor mental health.
Christian Guy, managing director at the Centre for Social Justice said: "Timid politicians are becoming numb to Britain's sky-high family breakdown rates. Yet, as these OECD figures show, broken families are not some inevitable feature of modern society or 'social progress'.
"All kinds of transformational help can be offered to parents and couples when they come under life's pressures," he added.