Having arrived in France in 1921, the young student of French, Komatsu Kiyoshi,, made the acquaintance of Ho Chi Minh. While briefly noting Komatsu's career as litterateur through the French Popular Front years, this article brings to light the nature and depth of Komatsu's relationship with Ho Chi Minh, especially as revealed by French police documentation. Komatsu’s links with communist and anarcho-syndicalist networks in Paris – Japanese included – and his surprising memoir of Ho Chi Minh published in a Hanoi newspaper in 1944 casts new light on both men and the relationship between Vietnam and Japan.