The 41-year-old was walking in Alexandra Parade, near to William Hills bookmakers, when she was threatened by two men.
It happened at around 1.55pm on Monday.
One man claimed he had a gun, but no weapon was seen.
The pair grabbed a white polythene bag from the woman, which contained a four-figure sum of cash. Police said the suspects made off towards Armadale Street.
Both men are described as white and around 25.
One was wearing a grey tracksuit with the hood up and black gloves. The other was wearing a navy blue tracksuit and pink gloves.
Detective Constable Gary Cassidy said: "It's possible these men were hanging around the area prior to, or following the crime.
"Perhaps you noticed the man wearing pink gloves. If you saw anything suspicious, please get in touch with us. Your information could be vital to our investigation."
Anyone with any information is asked to contact police on 101.