A woman known in her social network as "Captain Notto" has admitted that she has simply been wearing a uniform and pretending to be in the army for the past two years.
Piyamaphon Duangart said she had been living a lie ever since being deceived by people who claimed they could get her into the army after accepting money from her father.
The Royal Thai Army is now investigating whether Second Lieutenant Piyamaphon, 24, is a real officer. She claimed in her Instagram of being a military officer working in the Office of the Army Secretary.
For the past two years Ms Piyamaphon had told people around her that she was a military officer but on Friday she admitted she was not.
The native of Si Sa Ket province said her late father had wanted her to be a soldier. He contacted some officers working with Gen Sathien Permthong-in, the former permanent secretary in the Defence Ministry, to help get her into military service.
She submitted all the necessary documents and was informed that she definitely would be recruited and would start working in the Office of the Army Secretary.
Her father paid "quite a large sum" of money to people he believed would help get his daughter into the military, she said.
Months passed without further progress and then her father died. Ms Piyamaphon later approached the people her father had paid. They took her to Bangkok and provided her with a second lieutenant's uniform and then arranged for her to attend several social functions.
Ms Piyamaphon was told that when been asked about her job, she should reply that she works with the Office of the Army Secretary.
At the time she believed that she had already got the job, but later when Gen Sathien was replaced in August 2012, the people she had been in touch with told her that they could not get her into the military.
By this time, she said, many people already believed she was an army officer so she decided to continue the fiction. However, some people questioned her true identity and lodged a complaint with the army.
"I want my case to be a lesson to others so they don't get deceived like me," she said.