New South Wales Liberal MP Pru Goward has backed teachers at Goulburn Jail facing the sack because of a State Government plan to overhaul education in prisons.

In May, Corrections Minister David Elliott announced a plan to cut the number of teachers in jails from 152 full-time positions to 20.

The Government will create 60 new roles, which will not require teaching degrees.

Mr Elliott said prison teachers were "inflexible" with their working hours and that was one of the reasons for the restructure.

"Under the current system, there are limited teaching hours available in December-January, April and July," Mr Elliott said.

"Of the hours that are potentially available, only 62 per cent are used."

However, Mr Elliott's Liberal colleague Pru Goward defended the 10 teachers who work at Goulburn Jail, which is in her electorate.

"I am backing my teachers; they voluntarily went to a 48-week teaching year when asked in February," she said.

"They are skilled numeracy and literacy teachers and make a difference to the lives of the prisoners they educate."

Ms Goward lobbied her Cabinet colleague to change his mind.

"My formal meeting with the Minister was today and he has told me it is being closely examined," she said.

"It was a very constructive meeting with the Minister and Departmental officials, and he has undertaken to look at my proposal."

Cuts a 'high risk strategy': teachers union

Despite opposition from Ms Goward, Mr Elliott said the reforms were going ahead.

"Education programs are not being cut, but will be expanded and delivered by an external organisation monitored by Corrective Services NSW," he said.

"It will more than double the number of inmates completing literacy and numeracy courses to 1,840 per annum."

The NSW Teachers Federation argues only teachers have the skills to help inmates, many of whom have low literacy levels, complex psychological issues and learning difficulties.

Teachers Federation Organiser Rob Long said: "If this is just about cost-cutting it's a disaster, it's a very very high-risk strategy."

"We know you need really experienced, highly qualified teachers in jails in order to rehabilitate people," he said.

Social Justice Commissioner for Aboriginal Torres Strait Islander People Mick Gooda is backing the union in its fight to retain teacher numbers in jails.

"It's just not a job everyone can do, you can't pluck people off the streets to do this," he said.

"We know that Aboriginal people are incarcerated at a greater rate than anyone else in this country and I just wonder whether this is going to work in the long term."