One in five secondary school principals are working more than 60 hours a week, according to the National Association of Principals and Deputy Principals.
It's survey found 3 in 4 principals are spending more than 30 hours a week on admin, which it says is contributing to the recruitment crisis in the sector.
At its annual conference today, the NAPD is highlighting issues with retaining and attracting teachers, as many posts lie vacant.
But Education Minister Norma Foley says there are thousands of teachers entering the sector.
