The ministry confirmed it in a statement on Tuesday afternoon. "Our Embassy in Bangkok is currently providing consular assistance to the family of the deceased," it said.
"We extend our deepest condolences to the bereaved family for their loss. We are deeply saddened by this development, and reiterate our strong condemnation of this indiscriminate act of violence."
Police Major General Dr Pornchai Suteerakune, commander of the Institute of Forensic Medicine, told The Straits Times that she died on the spot.
It is understood that the woman's husband and brother were injured in the blast.
MFA added that Chua Siew San, Singapore's Ambassador to Thailand, visited injured Singaporeans at the various local hospitals on Tuesday morning.
All are receiving medical attention, while those with light injuries have been discharged.