Anybody moving to the UK and wanting to become a British citizen must pass the test.
It covers topics such as UK values, history, law, and society.
But researchers at Essex University put more than 270 people, nearly all UK citizens themselves, to the test and found over two thirds failed.
Before taking the test, many felt it should be made harder and conservative leaning voters in particular over estimated how well they would do.
Academics found there were no significant differences in test performance across the political spectrum.
Having sat the test most, regardless of their political leanings, changed their mind and felt it should be made easier.