The Niitaka-class cruisers were ordered by the Imperial Japanese Navy under its 2nd Emergency Expansion Program, with a budget partly funded by the war indemnity received from the Empire of China as part of the settlement of the Treaty of Shimonoseki ending the First Sino-Japanese War. The class was intended for high speed reconnaissance missions. Tsushima was the first ship to be built by the new Kure Naval Arsenal, located at Kure, Hiroshima. 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 keellaid down on 1 October 1901 and launching on 15 December 1902. Tsushima was not completed until 14 February 1904.
Design
In terms of design, Tsushima was very conservative in layout and similar to, but somewhat larger than the earlier Japanese-designed. 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. In terms of armament, it is noteworthy that Tsushima was not equipped with torpedoes. 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. The main battery was standardized to the QF 6 inch /40 naval gun found on most contemporary Japanese cruisers. The Niitaka-class cruisers were fitted with 16 Niclausse boilers, a great improvement on the locomotive boilers of the Suma class.
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. 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. On 15 August, Tsushima and pursued the, which she fought at the Battle of Korsakov. During the duel, Tsushima scored 14 hits on Novik, but was holes under her waterline by a shot from Novik and was forced to stop for repairs. She did, however, assist in the rescue of Russian sailors off Novik after the battle. At the crucial final Battle of Tsushima on 27 May 1905, Tsushima was part of the Japanese squadron attacking the Russian cruisers, and as well as the already heavily damaged battleship. Tsushima took six hits during the engagement, which killed four crewmen and a senior officer. On 28 May 1905, Tsushima took part in the final combat of the battle against the cruiser. After the war, Tsushima was assigned patrol duties off of the China coast.