 Juntree began his career as a civil servant in the Mineral Fuels Division (now the Department of Mineral Fuels of the Ministry of Energy) of the Thai government.He began writing novels and science-related articles in limited circulation as a senior high school science teacher at the Kenneth Mackensie School in Lampang Province.In 1945, he collaborated on the magazine "Witthayasat Mahatsachan" alongside Dr Preecha Amatyakul, then Assistant Secretariat of the Science Society of Thailand.