At the age of three-and-a-half, her parents presented her to Queen Saovabha Phongsri, who gave her the name Poonsapaya, and placed her under the care of Princess Valaya Alongkorn.

She had begun a doctorate at the University of Wisconsin–Madison when Thailand joined World War II against the United States.

The government ordered her return, but she decided to join the Free Thai resistance movement as a radio broadcaster assisting the Allies instead.

Poonsapaya served as its dean—the first woman in Thailand to hold such a position—until her retirement fourteen years later, after which she continued teaching as professor emeritus.

The Chulalongkorn University Demonstration School was also established for teacher training and education research under her leadership.

[6] She and her husband, Mom Luang Chirayu Navawongs, whom she married in 1952, also contributed to various other charitable causes (they had no children).

She was appointed Dame Grand Commander of the Order of Chula Chom Klao in 1986, granting her the title Thanphuying.