Launched in 1926 and heavily modernized in 1938-40, Aoba initially served as a patrol craft, largely along the China coast, and saw extensive service during World War II.

Repeatedly heavily damaged and repaired, she was finally crippled by bombing and settled on the bottom of shallow Kure harbor in April 1945; two raids in late July reduced her to an unsalvageable hulk.

During the attack on 24 July 1945, future Vice admiral Dick H. Guinn dropped the 2,000 lb (910 kg) bomb which contributed to her sinking.

[2] Named after Mount Aoba, a volcano located behind Maizuru, Kyoto, she was formally removed from the Navy List on 20 November 1945, and her wreck scrapped in 1946–47.

She displaced 8,300 tons (standard, 9,000 final), was 185.17 metres (607 ft 6 in) long, and carried a main battery of six 20 cm/50 3rd Year Type naval guns in three twin turrets, two forward and one aft.

Aoba was extensively modernized at Sasebo Navy Yard from 1938 to 1940, receiving new torpedo tubes, enhanced anti-aircraft guns, improved fire controls and better aircraft facilities.

The following day, 8 May 1942, 46 SBDs, 21 TBDs and 15 Grumman F4F Wildcats from Yorktown and Lexington damaged the aircraft carrier Shōkaku severely above the waterline and forced her retirement.

On 7 August 1942, an Aichi E13A1 "Jake" from Aoba spotted "one battleship, one auxiliary carrier, four cruisers, seven destroyers, and fifteen transports" off Lunga Point near Tulagi.

In the Battle of Savo Island on August 9, 1942, CruDiv 6, Chōkai, light cruisers Tenryū and Yūbari and destroyer Yūnagi engaged the Allied force in a night gun and torpedo action.

At the Battle of Cape Esperance on 11 October 1942, CruDiv 6's cruisers (Aoba, Furutaka, and Kinugasa), and destroyers (Fubuki and Hatsuyuki) departed Shortland to provide cover for a troop reinforcement convoy by shelling Henderson Field on Guadalcanal.

So alerted, the radar-equipped American cruisers USS San Francisco, Boise, Salt Lake City, and Helena and five destroyers steamed around the end of Guadalcanal to block the entrance to Savo Sound.

Both fleets opened fire, but Admiral Goto, thinking that he was under friendly-fire, ordered a 180-degree turn that exposed each of his ships to the American broadsides.

On 3 April, while moored at Kavieng, New Ireland, Aoba was bombed by Boeing B-17 Flying Fortresses of the Fifth Air Force's 43rd Bombardment Group.

A direct hit on Aoba caused two Type 93 Long Lance torpedoes to explode and set the ship on fire while the B-17s strafed the decks with machine guns.

The ship remained based out of Singapore to the end of February 1944, escorting supply convoys to Burma, the Andaman Islands and along the Malaya coast.

Aoba limped into Cavite Navy Yard near Manila, but while under emergency repairs the following day and on 29 October the ship was bombed by carrier-based planes from Task Force 38.