Almost 30% received the coveted higher marks, with pupils performing well in sciences, maths and art and design. However at the very top mark they lagged slightly behind the average across the three countries.
A one-off rise in the number of pupils taking film or media studies was linked by the Joint Council for Qualifications (JCQ) to the filming of the Game Of Thrones fantasy drama in Northern Ireland.
However the number of political studies A-level entries over the one year was down by a fifth, a decrease of 223.
Children went online from countries as diverse as Oman, Hong Kong and the United States to receive their grades from early this morning. Almost 24,000 logged on first thing this morning.
Aoife Malone, 18, from Co Armagh, was celebrating after being awarded two A*s and two As and will go to teacher training in Belfast. She said: "I never dreamt I would get that. I worked hard but you don't think you will get that."
Results overall remained fairly stable, with a slight increase in the percentage receiving the top A* grade, rising to 7.3%, JCQ said. That compares to 8.2% across Northern Ireland, England and Wales.
At A*-A there was a slight increase of 0.8% from last year to 29.9%. That compares to 26% averaged across Northern Ireland, England and Wales. Almost half of maths entrants in Northern Ireland achieved that standard.
The number of A-level subject entries dropped by 3.8% from almost 33,000 last year to 31,600 this time, expected to be a short-term change. Girls again outperformed boys in winning top grades.
The most popular A-level subjects overall included biology, maths, religious studies, history and English.
The percentage achieving grades A*-C was 83.7%, and 98% earned at least a grade E.
Girls outperformed boys in achieving the top grades. The most popular subject for boys was maths while for girls it was biology.
This year saw the highest number of AS-level entries since the qualification's introduction in 2001, in line with the rising population.
A quarter achieved an A and three-quarters at least a C.
Stormont education minister John O'Dowd said: "Every pupil is different and they stand the best chance of succeeding if they follow courses that interest and inspire them.
"Pupils here continue to perform particularly well and I am delighted to see STEM (Science, Technology, Engineering and Mathematics) subjects such as biology and maths ranking amongst the most popular choices for pupils."
Jarlath Burns, principal at St Paul's High School in Bessbrook, Co Armagh, said teachers were working closely with employers to ensure pupils had the skills to succeed in a workplace which included major local industries like veterinary pharmaceuticals firm Norbrook Laboratories.
"We are absolutely delighted, we think it is our best year ever."
Chris Keates, general secretary of the largest teaching union in Northern Ireland, NASUWT, said standards had been maintained across the board.
"Credit must go to teachers who have, yet again, pulled out all the stops to ensure that young people are supported to achieve their best.
"That teachers have achieved these results despite savage pay and funding cuts, job losses and the continuing uncertainty over the future of the A-level system in Northern Ireland is a testament to their dedication and skills."
GCSE and A-level exams in Northern Ireland are to remain largely unchanged.
Mr O'Dowd's decision came after the former education secretary for England and Wales said he would introduce dramatic changes to the way they conduct their exams, meaning they come after two years study rather than at intervals during the course.
COMMENT RULES: Comments that are judged to be defamatory, abusive or in bad taste are not acceptable and contributors who consistently fall below certain criteria will be permanently blacklisted. The moderator will not enter into debate with individual contributors and the moderator’s decision is final. It is Belfast Telegraph policy to close comments on court cases, tribunals and active legal investigations. We may also close comments on articles which are being targeted for abuse. Problems with commenting? firstname.lastname@example.org