Gun City owner David Tipple suspects the people in this CCTV footage of stealing nearly $20,000 worth of items from his Christchurch store.

A man with a "cheesy grin" is suspected of taking up to $20,000 worth of goods from a Christchurch gun shop.

Gun City posted CCTV footage online of a man it claims stole several items from the store on Sunday afternoon.

Owner David Tipple hoped it might lead to the alleged thief being caught.

GUN CITY Gun City owner David Tipple wants to find this man and woman after a theft on Sunday.

Tipple said the man arrived at the store with a woman at 2.45pm on January 10. They moved around the shop before leaving after 3pm.

"They walked out with big cheesy grins," Tipple said.

Staff were unaware of the theft until they did a routine security footage check the next morning.

A $18,000 night vision head unit was among the stolen items.

CCTV footage showed the man, who wore a black puffer jacket, leaning over a counter and taking an item. He then moved to a clothing rack and allegedly stuffed the item inside his jacket.

"I think he has chosen the most expensive thing he could steal."

Tipple said such incidents were "very uncommon".

"Dishonest people don't normally risk coming into a gun shop."

Tipple hoped the Facebook posts might lead to a return of the stolen items.

"If you don't get on to it immediately you've missed the boat."

A police spokesman said they would follow up on any leads from the CCTV footage.

"If anyone has any knowledge of it, via whatever sources, then we would love to hear from them," he said.