The marsupial, native to the wilds of Australia, has been captured on camera phone by Kirsty Johnson.
She was driving by Somerford Common towards Dauntsey at around 11am on Tuesday when she spied the wallaby among the trees by the side of the road.
"I pulled over and got out of my car, and tried to take a decent picture before it bounced off.
"I have seen them here a few times recently.
"I have tried to take a picture when I was on foot, but they are quite shy, and disappear really quickly."
This time, the Wiltshire wallaby hung around long enough for a picture.
"It was right in front of me, and staring right at me," she said.
Kirsty, 36, who lives in Minety and works as a professional dog walker for Wheelers Walkers, said she had seen the wallaby about three times, always in the morning.
She was not sure if it was the same wallaby or if there is more than one of them.
"It's always in the same area of the common," she said.
Kirsty described the wallaby as about the size of a deer, and able to move quickly.
She posted the picture on social media, and her wallaby spotting attracted lots of interest and comments.
"A lot of locals have seen the wallaby around," she said. "But it's not something you see every day is it? And it's rare to get a good picture of them. That's why I shared it.
"It's proof its not just a rumour."
Just a few weeks ago, another driver had a surprise when she saw a wallaby hopping across the road - for the second time in the same place.
Danielle Mewis was heading to work just before 8am when the Australian native popped out from the side of the road near the common.