Millennials, or those born between 1981 and 1996, are more disillusioned than Generation X, those born between 1965 and 1981, or Baby Boomers born between 1944 and 1964 and the Interwar Generation of 1918-1943.
"Across the world, younger generations are not only more dissatisfied with democratic performance than the old, but also more discontented than previous generations at similar life stages," the Cambridge study found.
The picture is bad in the United States, Brazil, Mexico, South Africa, France, Australia and the United Kingdom.
But satisfaction has increased in Germany, South Korea and many of the post-Communist countries of Central and Eastern Europe.
The main reason behind the disillusion with democracy among young people was inequality of wealth and income, the report said, citing figures showing that Millennials make up around a quarter of the U.S. population but hold just 3% of the wealth. Baby Boomers held 21% of the wealth at the same age.
The study suggested that the populist challenge to mainstream, "establishment" politics could actually help improve democratic engagement by shocking moderate parties and leaders into reversing the decay.
The Cambridge Centre for the Future of Democracy delved into data from over 4.8 million respondents collected across 160 countries between 1973 and 2020.