Due to lack of experience by the builders, Tsushima took an extraordinary long time to compete, despite her small size and relatively simple design, with the keel laid down on 1 October 1901 and launching on 15 December 1902.

The increased displacement, heavier armor and lower center of gravity resulted in a more seaworthy and powerful vessel than Suma, and enabled Tsushima to outclass many other contemporary protected cruisers.

Observing problems experienced by the United States Navy during the Spanish–American War with torpedo reliability and the dangers of sympathetic detonation, it was decided not to use this weapon on the new cruisers.

[2] Tsushima was commissioned during the middle of the Russo-Japanese War, but she was present with the 4th Detachment of the Japanese 2nd Fleet and participated in the shore bombardment of Russian positions during the Battle of Port Arthur on 9 March 1904.

[3] From April, she was assigns to patrols of the Korea Strait and the Sea of Japan, but was not in position to participate in Battle off Ulsan on 14 August 1904.

However, she was reassigned to the First Southern Expeditionary Squadron based in Fiji from December 1914 to protect British shipping around Australia and New Zealand from German commerce raiders and U-boats.

From mid-1915 to 1918, Tsushima and her sister ship Niitaka were permanently based at the Cape Town, assisting the Royal Navy in patrolling the sea lanes linking Europe to the east.