Greens leader Shane Rattenbury said as it stands, people "simply have to state a reason" why they want an extra firearm and can have the same reason on every permit.

He said he would be sitting down with his cabinet colleague and Labor police minister Mick Gentleman to discuss how the procedure could b tightened up.

"We need to have a close look at whether our protections are adequate here," Mr Rattenbury said.

"The ACT Greens are concerned about the figures we've seen on the number of guns we see in ACT suburbs. We see quite a few households across the territory with a number of guns, the question needs to be asked why does someone need an arsenal like that?

"The Greens believe there are legitimate reasons for households to have guns particularly in a rural environment and the sporting shooters but we need to make sure we're being rigorous about making sure people don't have unnecessary arsenals in our suburbs."

Data released to the NSW Greens under freedom of information revealed the southside suburbs of Bonython, Calwell, Chisholm, Gilmore, Isabella Plains, Richardson and Theodore had 2199 registered firearms.

The postcode with the next highest concentration was that of Belconnen, Bruce, Evatt, Giralang, Kaleen, Lawson and Mckellar, with 1565 registered guns.

The most guns belonging to one person in Canberra was 54. The data excluded gun dealers and collectors.