Purísima Concepción, was a Spanish first-rate ship of the line of the Kingdom of Spain's Armada Real in service between 1779 and 1810.

[4] The name Purísima Concepción translates into English directly as Immaculate Conception, a religious reference to the veneration of the Virgin Mary.

She was designed by Spanish naval architect Francisco Gautier and constructed by José Joaquín Romero Fernández de Landa.

Purísima Concepción was recorded as having been at Cádiz in 1780, her first action involved attachment to the 3rd Franco-Spanish fleet for the Campaign of the English Channel.

[2] On 22 October 1782, Purísima Concepción was one of 38 ships of the line of the Spanish fleet at the Battle of Cape Spartel though she did not see any action that day.

On 13 August 1784, she left Cartagena in a patrol squadron together with the sixth-rate, 24 gun frigate Santa Gertrudis returning to Cádiz.

The action lasted around a half-hour beginning when Purísima Concepción opened fire on the Algerian ship at around 10 o'clock in the morning.

Her commander was Lieutenant-General Francisco Javier Morales de los Ríos and her Flag Captain & Brigadier was José Escaño.

The Spanish defeat at Cape St. Vincent enabled the British Royal Navy under Admiral Horatio Nelson back into the Mediterranean Sea.