Haruhi Nanao is a Japanese voice actress born on February 11, 1973, in Tokyo, Japan. She is affiliated with the talent agency 81 Produce. She began her career in 1997 and was previously known by the stage name Haruhi Terada, later changing her surname to Nanao, her mother's maiden name.

Nanao has built an extensive career with a wide variety of roles in anime television series, original video animations (OVAs), theatrical films, and video games, as well as voice work for foreign live-action and animated dubs. Her early roles include Pepper in One Piece, Mai Kujaku in Yu-Gi-Oh! Duel Monsters, and Ai in Digimon Tamers, among many others. She also played Kana Sohma in the 2001 version of Fruits Basket and Ranamon in Digimon Frontier.

Throughout the 2000s and 2010s, she continued to secure prominent roles, including Kasumi Aono in the Rosario + Vampire series, Cybela Coutaud in Tengen Toppa Gurren Lagann, and Rin Nohara in Naruto Shippuden. She took over the role of Midori Yoshinaga (later Ishizaka) in the long-running series Crayon Shin-chan starting in 2009.

A significant and recurring role in her career is that of Aeka Masaki Jurai in the Tenchi Muyo! franchise. She first voiced the character in the 2014 television series Ai Tenchi Muyo! and later reprised the role for the fourth OVA series, Tenchi Muyo! Ryo Ohki (2016). Another notable recurring role is Sella, the dedicated homunculus maid to Illyasviel von Einzbern, in the Fate franchise. Nanao has voiced Sella across several anime adaptations, including Fate/kaleid liner Prisma Illya 2wei, its sequel 2wei Herz!, and Fate/stay night: Unlimited Blade Works.

Her filmography also demonstrates frequent work in the Future Card Buddyfight franchise, where she voiced multiple characters such as Hanae Jumonji, Stella Watson, and Suzumi Mikado across different series. In 2020, she was cast as Lamda in the series AMAIM: Warrior at the Borderline UltraSteel Ogre-Gear. Beyond anime, her extensive dubbing work includes providing the Japanese voice for Dawn Summers, played by Michelle Trachtenberg, in Buffy the Vampire Slayer.