維新帝
In 1906, he joined the Progressive Movement (Duy Tân) led by Phan Chu Trinh (1872–1926), Huỳnh Thúc Kháng (1876–1947) and Trần Quý Cáp (1870–1906). Phan Khôi moved to Hanoi to learn French and Quốc ngữ (Vietnamese written in the Latin alphabets).