On 12 February 1901 the 1st East Siberian Artillery Brigade was subordinated to the 1st Siberian Army Corps. With the beginning of hostilities during the Russo-Japanese War, on 30 January 1904 the brigade (at the time consisting of four batteries) became part of the Russian Manchurian Army. Later on 15 February it was renamed the 1st East Siberian Rifle Artillery Brigade. Around this time the 2nd battery formerly of the 23rd Artillery Brigade became part of the unit. The brigade, along with its corps, later became part of the 1st Manchurian Army. In the war against Japan it took part in the Battle of Te-li-Ssu (14—15 June 1904) and in the Battle of Mukden (20 February—10 March 1905). At least one officer of the brigade was awarded the Order of St. George during the war. On 19 February 1906 it was transferred to peacetime status and remained as part of the 1st Siberian Army Corps. In 1907 it was reformed, with the batteries being organized into two divisions of three batteries each. In September 1910 the unit was renamed the 1st Siberian Rifle Artillery Brigade and was made part of the 1st Siberian Rifle Division. In addition, it received the former East Siberian mountain artillery division.