Thanadda Sawangduean, 42, won the women writers' Chommanard Book Prize for her recently published autobiography "I am Eri: My Experience Overseas", an account of her years on the game.
Her work took her from the Thai beach resort of Pattaya to Hong Kong and then to Japan, where she was jailed for possession of drugs.
"I wanted to share these experiences so they can be a lesson for those who want to take the wrong path," Thanadda told the Bangkok Post newspaper.
The panel said they chose Thanadda's book for the "unusual" approach of tackling a much-discussed subject first hand, rather than from the perspective of an observer.
Thanadda said she was inspired to write her book by her American boyfriend Dave.
Her prize consisted of 50,000 baht ($1,667) and a diamond brooch.