One in two will have never been in paid work, Dutton said.
"It's not a reflection on people we are bringing in now but we have to recognise facts that people come here without formal education and without skills and we provide funding to improve their skills and that's a good thing," he said.
The minister accused Labor of plucking a number out of thin air with its plan to increase the refugee intake to 27,000 a year and was scathing of the Greens policy to take 50,000.
The coalition supports an increase from 13,750 now to 18,750 by 2018/19.
Dutton said the Opposition hadn't done enough homework to spell out how it would provide resettlement services.
Resettlement costs would increase to A$1 billion ($1.1 billion) under Labor and A$7 billion under the Greens' plan, Dutton said.
Former Liberal Immigration Minister Amanda Vanstone said Australia should be proud it accepts illiterate and innumerate refugees for resettlement because it gives girls an opportunity for an education.
- AAP