Graduating will allow the men to take part in other programmes, such as industry training or treatment programmes.
"It will help them find a job on release," Ryan said.
"We know that with stable employment, offenders are less likely to reoffend, and that means there are fewer victims.
"It will also improve their relationship with their family, if prisoners can read a story to their child or write a letter to them."
Corrections Minister Louise Upston was on hand to present the men with their certificates.
In a speech, she told them "I'm not interested in your past. I'm very much interested in your future."
Afterwards, she told media that from the moment people arrive in prison, there had to be a focus on the rest of their life.
"So giving them skills, and giving them employment opportunity, sets them up for a different kind of future".
Upston has put Corrections on notice that she wants the education programmes to keep growing.
"I've said to them, of the areas that are within your control, I want you to do more right now.
"They're rising to that challenge, which is great.
"I'm expecting there will be more participating in literacy and numeracy, more in NCEA, more in trades training."
One prisoner, whose name is not being printed in order to respect victims of crime, said he was proud to achieve his numeracy certificate.
"It's not just for me, I'm doing it for my grandchildren.
"I have eight of them. Now when I get out, I can spend some time with them."
He said the certificate was a chance to change mistakes from his past.
"I did two years of high school, and my favourite subject was maths.
"And now I've got my numeracy. It's up to level five."
The Intensive Literacy and Numeracy Everyday Skills Programme has had 884 prisoners enrol since it started in 2015/16.
It's currently available in 16 Corrections prisons.
It includes interactive activities, educational games, and one-on-one time with a tutor, in a bid to ensure prisoners engage and remember the lessons.
