The percentage of top grades in Northern Ireland was 31.9% — 5.4 percentage points higher than England and 7.3 percentage points higher than Wales.
And just 1.9% of entries here failed to get an A-Level pass.
But the proportion of Northern Ireland pupils earning A* and A grades has fallen for the second consecutive year — down from 34.5% in 2011 and 35.9% in 2010.
Anne Marie Duffy, director of qualifications at the Council for the Curriculum, Examinations and Assessment, Northern Ireland's exam body, said: “Over time results can fluctuate and this year we have seen a small decrease in the percentage of entries gaining the top grades.
“This is in line with expectations, based on predicted performance for this group of students, and their performance in last year's AS-Level exams.”
The falling standards are because more teenagers with a wider range of abilities are staying on at school as a result of the economic downturn and the lack of employment opportunities.
Ms Duffy added: “As the size of the group taking A-Levels has grown, the range of ability of the students taking the exams has widened too. In these circumstances the performance of our students continues to be very pleasing.”
As in previous years Northern Ireland girls outperformed boys.
Employment figures published on Wednesday show Northern Ireland has the highest rate of youth unemployment for 18 to 24-year-olds in the UK.
There are now 22,000 young people out of work who want a job and 18,877 of them claiming unemployment benefits.
That has led to a record level of entries for A-Level exams here, despite a downward trend in pupil numbers.
Education Minister John O'Dowd said: “It is encouraging that more pupils are continuing on with their education after the age of 16 and I hope that this trend will continue in the coming years.”
JCQ figures show there was a record 32,908 entries for A-Levels here. This marks a 10% rise in entries over five years. During the same period the proportion of students staying on to A-Level has risen from 47% to 57%.
Professor Richard Barnett, vice-chancellor of the University of Ulster said: “One explanation is, of course, the recession. In the world of the future, jobs and careers will increasingly go to more highly skilled people, and it is the higher education sector that will enable Northern Ireland's young people to effectively compete.”