Officers were called to the currency exchange, near the Dolphin Circle at the western end of Phra Barami Rd, at 12:11am.
The staffer at the currency exchange, Phattharanit Suphan, told police that a man had arrived at the kiosk and attempted to steal cash kept in a cabinet.
He was wearing a mask. The Phuket News has been given no other description of her attacker.
Ms Phattharanit screamed for help, but the man placed his hands around her neck and began strangling her.
As people nearby arrived to help, the man fled. He was last seen heading down a nearby alley.
The man fled without taking any of the cash kept at the currency exchange.
Police are now actively searching for the man.