Azucena Díaz is a Spanish voice actor based in Barcelona, primarily known for her work in dubbing foreign productions into Spanish and Catalan for distribution in Spain. She is the daughter of Joaquín Díaz, and was previously credited under the name Asunción Díaz. Her first role in dubbing was as a child, and she has remained an active professional in the field, with a career that also encompasses dubbing direction, advertising voice-overs, and narration. Her usual voice type is characterized as medium, and she is fluent in both Spanish and Catalan.

Díaz has built an extensive filmography in animation, with several notable credits in anime. One of her most recognized roles is providing the voice of the Shinigami Rem in the Barcelona dubbing of the series Death Note. She reprised this role for the compilation film Death Note Relight: Visions of a God. In the same franchise, she also voiced Sachiko Yagami, the mother of the protagonist Light Yagami.

Her other significant anime voice work includes the character ADA in Ingress: The Animation. She has also voiced roles in various other anime productions, such as Maya in Buddha 2: Tezuka Osamu no Buddha - Owarinaki Tabi, the characters Bruja and Reina Euforia in Glitter Force, and roles in Grave of the Fireflies, where she voiced both the Aunt and Tieta. Her filmography further includes parts in Rayearth, Hello! Sandybell, 3x3 Eyes Seima Densetsu, and Andromeda Stories.

Beyond her work as a voice actor, Díaz has also worked as a dubbing director. For example, she directed the Spanish dubbing for the series Maison Ikkoku in 2006 at the Dubbing Films studio. Her work is primarily associated with studios in Barcelona, where she continues to be active in the industry.