More than 8,000 litres of alcohol brewed in New South Wales prisons has been found in a haul of contraband seized by prison authorities.

Data obtained by the State Opposition under Freedom of Information laws showed that 170 kegs' worth of prison-brewed alcohol was made by inmates right under the noses of guards in 2015.

Other items confiscated included 86 weapons, 85 mobile phones as well as bags of marijuana, steroids and the drug ice.

Labor's corrections spokesman Guy Zangari said the amount of contraband was a symptom of an overstretched prison system.

"This simply tells us that the system is in complete chaos," Mr Zangari said.

"Overcrowding is the biggest issue and what this is leading to is the fact that staff can't do their job properly because they are spread thinly across the ground."

He said the fact that prisoners could brew alcohol, undetected by guards, showed how lax supervision could be under the current conditions.

"This is an extraordinary figure that has come to light … 8,604 litres of brew," he said.

"Anyone who has ever made home made brew or homemade wine would know it takes a lot to do, so these are very delicate operations and clearly the prisoners are getting away with it."

Winning 'war on contraband': Minister

But Corrections Minister David Elliott said he was pleased with the haul, arguing it showed authorities were winning "a war on contraband".

"I'm delighted to see that so much contraband has been removed from the state's prisons … and I'm delighted that with a record budget we are now implementing further reforms and new technologies which will continue with this fight against contraband," Mr Elliot said.

"Let's remember there has been a decline in the amount of contraband in New South Wales prisons."

He said that prison brew or "hooch" was an age-old problem.

"Home brew has been happening around the world illegally for centuries and anyone who can get their hands on fruit can brew their own alcohol," Mr Elliott said.

"Our job is to make sure that the fruit that is provided to our prisoners is consumed in the appropriate way and not stockpiled to make illegal alcohol."

The data also showed that visitors to the state's prisons were also caught with a large amount of contraband in 2015.

Amongst the items confiscated from visitors were more than 1,000 needles, 30 litres of alcohol, 40 weapons and 11 firearms rounds.