During the Russo-Japanese War, he advanced from the Yalu River to the Battle of Mukden fighting various battles along the way as the commander of the First Troop (Japanese Army), and the Russian army was afraid of him, calling him 'Kurokinsky' (after his family name Kuroki).
日露戦争では、第1軍(日本軍)司令官として鴨緑江から奉天会戦まで連戦し、ロシア軍からは、「クロキンスキー」と恐れられた。