[2] Starting in October 1934, Almirante Cervera participated in the bombardment of coastal targets during the insurrection in Asturias,[3] but it was at the time of the civil war where she took a leading role in naval operations.

[5] Once in service, she formed a task force with the battleship España and the World War I-era Alsedo-class destroyer Velasco to blockade the ports of northern Spain.

She was nicknamed El Chulo del Cantábrico, ("The dandy of Biscay"), because her almost unopposed activity both supporting Franco's army offensives in the north as well as intercepting Republican and international shipping.

British historian Hugh Thomas claims that when the Republican troops broke into the compound, the defenders asked Cervera to fire right on them.

[7] On 9 August, while firing on government positions, she hit by mistake the British yacht Blue Shadow, whose master, a former RAF officer, was killed.

After blunt exchanges between Hood and Cervera, the freighters slipped into Bilbao supported by the fire of a coastal battery and the Basque armed trawler Biskaya.

[16][17] On 4 July, in contrast, Cervera seized the French steamer Trégastel and drove off the British Latymer off Cantabria, when both ships attempted to enter Santander under the protection of the battleship Resolution.

A 50 kg (110 lb) bomb ripped through the stern funnel and although the fuse failed to explode, 25 men were wounded and the machine room damaged.

[22][23] On 6 March she was escorting a convoy and participated in the Battle of Cape Palos, where the heavy cruiser Baleares was torpedoed and sunk by Republican destroyers.

[26] Cervera continued her operations along the shrinking Republican coastline until the end of the war, but her role throughout the conflict was largely overshadowed by the heavier cruiser Canarias.