Police are looking for a woman who ran off with a dog owned by a vendor for The Big Issue in Adelaide's Rundle Mall.

Key points: An Adelaide vendor sells The Big Issue alongside her dog in Rundle Mall

An Adelaide vendor sells The Big Issue alongside her dog in Rundle Mall Her black and white chihuahua was stolen yesterday

Her black and white chihuahua was stolen yesterday Police have released CCTV footage of the suspect

Ruth Reidy's black and white chihuahua Fifi was wearing a white dress with black stripes and sitting in a pram outside Woolworths when she was stolen about 2:00pm yesterday.

Ms Reidy, 70, said she left Fifi in her pram at the supermarket's checkout area for two minutes, after finishing her shift.

"A lady said a woman came out of there wheeling the pram and running down the mall so myself and about three other women ran down the mall but she was completely gone," Ms Reidy said.

The small dog is a well-known sight in Adelaide's main CBD shopping strip.

"Everyone recognises her because when we come in she's sitting in the pram," Ms Reidy said.

"Everyone says 'Fifi, Fifi' and they go and talk to her and play with her.

"She gets out the pram and runs around — she likes coming in."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 28 seconds 28 s Police CCTV of a woman holding a dog crossing King William Street.

Police released CCTV from the corner of King William Street and North Terrace in the CBD showing a woman carrying a dog across the busy intersection.

A woman taking Fifi the dog from Rundle Mall. ( SA Police )

They described the woman as having dark hair, wearing a black cap, a white top, black cropped jeans, sneakers and carrying a pink backpack.

The pram was recovered yesterday afternoon.

Ms Reidy said she had been "praying to God" for Fifi's return.

Fifi and Ms Reidy featured in The Big Issue's 2019 calendar.

The magazine — which gives homeless and disadvantaged people a chance to help themselves by working as vendors — was first sold on the steps of Melbourne's Flinders Street Station in 1996.

In the two decades since then, the organisation has spread across Australia, with more than 500 vendors now working to distribute the magazine every fortnight.

The Big Issue state operations manager Matt Stedman said the organisation had been supporting Ms Reidy to get the word out about Fifi.

"I think the wider community recognises her and feel for her," Mr Stedman said.

"We're trying to support her to facilitate any way we can to get the word out."

Police have asked anyone who recognises the woman or knows of Fifi's whereabouts to contact Crime Stoppers on 1800 333 000.