Armed Forces Academies Preparatory Schoolis a military academy in Nakhon Nayok Province, providing an education equivalent to the last two years of senior high school. It is a flagship institution of the Royal Thai Armed Forces Headquarters. The curriculum consists of academic and physical training as well as other activities. Cadets who manage to graduate automatically gain entrance to the Chulachomklao Royal Military Academy, the Royal Thai Naval Academy, the Royal Thai Air Force Academy, or the Royal Thai Police Academy.

The school accepts only male applicants. Admission to AFAPS is selective. The number of applicants per year exceeds 70,000 and over 600 are accepted, making overall acceptance rate less than 1%. With more than 600 cadets per class year, the academy’s enrolment is around 2,000. The cadet regiment represents all provinces of Thailand. The academy supports the traditions and ceremonies of Buddhist, Muslim, and Christian students.