Police were informed of the incident, near the Diamond Cliff Resort, at 6:10pm.
The body of the woman, later identified as 23-year-old transgender woman Chananchida Wisetwongsa, from Roi Et, had been recovered and taken to Patong Hospital.
Ms Chananchida had walked down onto the rocks to take selfies with a friend. She posed too close to the edge of the large rock she was standing on and was swept into the water by a large wave, police explained.
Lifeguards were informed of Ms Chananchida’s predicament and rushed to recover her, but were too late to save her, police noted.
Ms Chananchida was pronounced dead at Patong Hospital.