He owned a Thai traditional medicine business and a general store in Kanchanaburi province, which had been passed to him by his father Mor Khein, a Thai traditional doctor. He was also a mayor of Kanchanaburi from 1942-45 during World War II. His public responsibilities brought him into contact with the Japanese troops in charge of building the Thai-Burma Death Railway. Boonpong got a contract from the Japanese to manage the canteen for POWs in the camp nearby, which allowed him to enter the camp with few restrictions.
After the war when rumors reached Britain in 1947 that Boonpong had fallen on hard times, three British POW camp commanders - Toosey, Knights and Lt. Col. Harold Lilly- launched an appeal among former Thailand prisoners of war. The appeal raised £35,000 and enabled Boonpong to start the Boonpong Bus Company, which flourished.
Boonpong's courage and compassion was later recognized by the British government, which honored him as a Member of the Most Excellent Order of the British Empire (MBE). The Netherlands also awarded him the Order of Orange-Nassau. Sir Edward 'Weary' Dunlop once praised Boonpong by quoting Shakespeare in Henry VI: "In thy face I see the map of honour, truth and loyalty." Initiated by Sir Edward, the Weary Dunlop-Boonpong Exchange Fellowship was was established in honor of two men in 1986, and continues through strong cooperation between the Royal Australasian College of Surgeons and the Royal College of Surgeons of Thailand.