Some security guards in one of Sydney's most popular shopping centres have used surveillance cameras to spy on unsuspecting female shoppers, saving images of the women to a secret shared file.

A Current Affair has revealed hundreds of women who visited Westfield Sydney in the city's CBD in the past 18 months have been filmed, filed and shared among a small group of security guards surveying them from a control room.

The guards are employed by SecureCorp, one of Australia's biggest security companies, promoted for its reliability and professionalism.

"We ensure billions of dollars of assets and the millions of people who use them every day are under our care and in safe hands," the company's website states.

Lawyer David Galbally QC said the conduct goes beyond an invasion of privacy.

"Those cameras are protected under legislation and these individual security guards are clearly breaching that, apart from the fact that they are clearly breaching their employment conditions," Mr Galbally told A Current Affair .

It is understood there up to 1000 images on file which have been categorised in regards to race, body type or clothing attire, including "Asian", "white", "cute", "legs", "blonde" and "hourglass".

"It's disgusting and it's racist in its highest form," Mr Galbally said.

"Categorising and singling out individual persons as to the way in which they look because of their colour and their race; it's absolutely appalling."

A Current Affair aired blurred footage of the women captured on CCTV, including teenage girls, and even mothers and their daughters.

A small group of security guards at Westfield Sydney have been using surveillance cameras to film and share images of unsuspecting female shoppers. (A Current Affair) (A Current Affair)

It's believed there are up to 1000 images of women on file. (A Current Affair) (A Current Affair)

One woman is filmed on an escalator; the camera then follows her to another escalator, where it then appears a security guard could be following her.

A Current Affair was provided the images by an unidentified individual who says they want the behaviour exposed.

"My hands are shaking. It's disturbing to me as an individual to know that somebody would have the intent of wanting to see me for their own purposes and really only a lustful purpose," a female shopper told A Current Affair.

"It's not even as if it's a couple of guys glancing at them every now and then. It's actually premeditated," another shopper said.

Psychologist Kaylene Evers says such behaviour is about power.

"It's a power trip for these guys. It's a sense of power of the women, and there is a sense of power from just being in the group," Dr Evers told A Current Affair .

She says the conduct may have started off as a joke, but has escalated to a point that a group began to build.

"Does it come to a point where they accost these women … where they revert to the cameras on the outside of the shopping centre and get number plates, who knows?" she said.

Mr Galbally says it is more than concerning when security cameras are used outside of their intended surveillance purposes.