The Russo-Japanese War had just started, and he served as a midshipman on the submarine tender Karasaki, and participated in the Battle of Tsushima aboard the cruiser Kasuga.

[1] Yoshida served as chief-of-staff of the Combined Fleet from December 1931 to September 1933 and was promoted to vice admiral on 15 November 1934, and Director, Bureau of Naval Affairs, within the Navy Ministry.

As Navy Minister, Yoshida was vehement in his opposition to signing of the Tripartite Pact between Imperial Japan, Nazi Germany, and Fascist Italy.

He was forced to resign due to illness and opposition to the pact on 5 September 1940, just before the arrival of the negotiating team from Germany, and the treaty went ahead despite his strong misgivings.

After the start of World War II, Yoshida was assigned a combat command, and took control of the China Area Fleet from November 1942.