The vast majority of the people of Scotland are satisfied with armed police on the streets, Kenny MacAskill told MSPs.
There is "no routine armed police force in Scotland" but Police Scotland has "officers routinely available" with firearms, he said.
Police Scotland has 275 officers — about 1.6% of the force — who can carry guns on everyday duty without the approval of a senior officer to fire, the Scottish Parliament has heard.
Prior to the creation of Police Scotland, firearms were only deployed on a case-by-case basis in response to a clear threat to public safety in five of the eight legacy forces.
Strathclyde, Tayside and Northern Constabulary had firearms officers routinely available across half of Scotland and this policy was rolled out nationwide at the advent of Police Scotland.
Opposition MSPs say this expansion amounts to "a change in the nature of our policing in Scotland" and that parliament should have been informed.
Mr MacAskill said he had no intention of reviewing the policy in response to MSPs' concerns.
Liberal Democrat justice spokeswoman Alison McInnes said: "We should be concerned here in parliament that the Justice Secretary hands the chief constable carte-blanche.
"Hundreds of officers have been given blanket permission to carry guns while undertaking everyday duty and crucially they no longer need the approval of the senior officer to fire those guns."
Labour MSP Graeme Pearson, former head of the Scottish Crime and Drug Enforcement Agency, called for a review. "I'm surprised at the casual nature of the cabinet secretary," he said.