The OECD survey measured the skills of 16-65 year olds in 24 countries and looked at how literacy, numeracy and problem-solving is used at work.
It involved 166,000 adults taking tests in 24 education systems, representing populations of 724 million people. From the UK, adults in England and Northern Ireland participated.
The study said it provides "clear evidence" of how developing and using skills improves employment prospects and quality of life, as well as boosting economic growth.
Andreas Schleicher, the special adviser on education policy to the OECD's secretary-general, warned of a "shrinking pool" of skilled workers.
'Car crash' for UK economy
When breaking the data down by country, the study found young adults in England scored among the lowest in the developed world in international literacy and numeracy tests. England is 22nd for literacy and 21st for numeracy out of 24 countries.
The OECD said the global economic race is strongly linked to educational performance and the report shows how the UK's share of the highest skilled workers is falling.
Director general of the Confederation of British Industry (CBI) John Cridland said the results are a "car crash in slow motion for the economy".
"You have about 30% of every year of 16-year-olds who have been failed by the education system," he said. "After 11 years in full time education, when they enter the labour force without adequate GCSE English or maths everyone loses out."
Important role for employers
Tata Consultancy Services HR director told HR magazine that employers should play a "very important role" in raising the skill level of young people entering the workforce.
"With so much to do and so many different groups pushing for more investment and attention, it is time to drill down further. We should no longer just be talking about STEM skills, we need to focus resources on the right areas," Mallick said.
"There needs to be a focus on giving young people the most employable skills, that will give the UK the best chance of producing the skills needed to drive economic growth."
The highest-performing countries for 16-24 year olds were Japan, Finland and the Netherlands. The country with the lowest numeracy skills was the United States.
Last year, the OECD warned that the US was almost the only developed country facing educational "downward mobility", where the younger population is less well educated than the older generation.
This latest study shows that the US once had 42% of the world's highest-skilled adults but this had now fallen to 28%.