Named locally as Joy Noah Williams, 24, she was found with incisions ready for tailbone surgery.
Surgeon Dr Sompob Saensiri, 51, has been arrested amid claims he was not qualifi ed to carry out the operation.
He has been charged with recklessness causing death and could face up to 10 years in prison.
Police were called to the SP Clinic in Bangkok on Thursday night to fi nd the woman lying dead on a bed.
Officers said she had stopped breathing after being given an anaesthetic and had a three-inch stitched incision at the base of her back after she asked for a “corrective procedure” to her tailbone area.
She had previously had liposuction at the clinic.
Dr Saensiri denies the charges and claims he treated the patient according to approved medical practices.
Officers are quizzing clinic staff to establish whether it was stocked with the correct life-saving equipment.
Thailand is the worldleader in cosmetic surgery tourism, with websites plugging deals promising ops at a 60% discount.
After the event, a Foreign Office spokesman said: “We stand ready to provide consular assistance.”
