The figures showed nearly half, 3689, were Pākehā, and 3285 were Māori.
Considered by gender, more than half, 4234, were boys.
At some schools, more than 30 per cent of school leavers last year had no qualification.
Considered by region, Gisborne had the highest rate of unqualified school leavers, at 19 per cent, followed by Northland and Manawatū with 15 per cent each.
However, at the level of territorial authority the percentage of school leavers with no qualification was 25 per cent or more in Ōpōtiki, Waimate, Ruapehu, Kawerau, and Manurewa.
Wellington had the lowest percentage of unqualified school leavers, at 8 per cent, followed by Nelson and Otago on 9 per cent.
Results for Māori students showed a stark contrast between English and Māori-medium schooling, with no NCEA qualification for 22 per cent of those leaving English-medium, and for 11 per cent of those leaving Māori-medium.
A quarter of the teens who left decile 1 schools, and a fifth of those leaving decile 2 schools had no qualification, as did 14 per cent of boys and 22 per cent of Māori.
A report on the figures said there was a lot of variation between schools.
"Some decile 1 and 2 schools have pass rates that exceed rates at some decile 9 and 10 schools," the report said.
The data showed more than 30 per cent of the students leaving some low-decile schools last year had no NCEA qualification, and at some high-decile schools the figure was about 15 per cent.
The president of the Secondary Principals' Association, Deidre Shea, said the increase in unqualified school leavers was worrying.
"Certainly the trend's going the wrong way, isn't it? Looking at the data on a national level, the number of leavers without qualifications at each of the [NCEA] levels seems to be on a slightly downward trend. It isn't a lot but it's enough that the trend is of concern."
Shea did not know what was causing the problem, but said it could be linked to increasing rates of absenteeism.
"The ministry has been concerned for a little while about the decreasing number of students, or proportion of students, who attend school regularly over the last few years," she said.
"Clearly I don't know, but I'd suggest that there may be a correlation there as well - so perhaps students not being as engaged along their journey in education."
Shea said she expected changes to the NCEA qualification would rectify the problem by making it a more motivating qualification for teenagers.
Spotlight on Gisborne
The Gisborne Region had the highest rate of unqualified leavers of any region, at 19 per cent.
The principal of Gisborne Boys' High School, Andrew Turner, said one of the reasons for the figure was the "truck load" of job opportunities in the region.
"There are more jobs in this region. They can't fill them with workers. So it's a really unique situation."
"I'm talking with employment people... they've got local industry here saying 'we'll take on apprenticeships for untrained, unskilled, as long as they're reliable and will turn up, we'll take them on', because they don't have enough workers. On the one hand that's really cool, that's really exciting.
"The negative side of that is what we're seeing is more and more of our young people getting to that 15, 16 years of age - 16 is the legal age to leave school - they turn 16 in the middle of their Year 11 year, they haven't got NCEA level 1; 'doesn't matter, I'm going to work, I can get $19.10 an hour, that's a priority for the family, that's more important'. Off you go."
Turner said the situation in Gisborne was a stark contrast to somewhere like Dunedin, where university and polytechnic students took most of the unskilled jobs, leaving most of the city's school leavers little option but to stay in school and then enrol in tertiary study.
He said Gisborne Boys' High School had an excellent careers team that helped students work on a qualification pathway, but it was hard to persuade some students to stay when they could find work.
Turner said another factor contributing to the figures was a relatively high rate of transience.
Ministry reasons
The Education Ministry's acting group manager of secondary- tertiary, Richard D'Ath, said the reasons for young people leaving school before attaining a qualification varied, but often had to do with the labour market and employment opportunities.
"Since 2015, the labour market has been strong and provided opportunities for young people. This may have led some young people to leave school early to enter the workforce."
D'Ath said the ministry and the Qualifications Authority were tracking how students were progressing this year, but they appeared to be performing at a similar level to last year once the impact of bonus "learning recognition credits" were taken into account.
