Yukiko Mizuochi is a Japanese voice actress, narrator, and singer from Tokyo, Japan, born on December 18. She is affiliated with the talent agency Arts Vision, having previously been represented by Kyuu Production. Standing 167 cm tall with blood type A, her hobbies include singing, trampoline, and bird watching, and she possesses skills in kyogen (a form of traditional Japanese comic theater) and bird imitation. She began her career after graduating from Tokyo University of Agriculture and working at a major company, later making the decision to switch professions and become a voice actor.

Mizuochi has built a career encompassing a wide range of roles in anime, video games, and Japanese-language dubs of foreign films and television dramas. Her anime roles are diverse, often portraying mothers and other supporting characters. A key early role was as Inertia's Mother in the 2005 film Kino no Tabi: the Beautiful World - Life Goes On. In 2007, she voiced Milk Usagi Okaasan (Kate Periwinkle) in the OAV series Sylvanian Families. She also took on roles in major productions such as Kazuyo Kusakabe, the mother of Mari, in the 2009 drama Tokyo Magnitude 8.0, and the mother of Sarah in the 2006 special Rozen Maiden: Ouvertüre. Her work in the early 2010s includes the role of Anyuta in the 2010 television series Cheburashka Arere?. More recent anime credits include Fumi Sugisaki in Healin' Good Precure, Eva Santos in Full Metal Panic! Invisible Victory, and roles in series like Fractale, Nourin, and Pandora in the Crimson Shell: Ghost Urn.

Beyond anime, Mizuochi's voice acting portfolio is extensive in other media. She has provided voices for numerous video games, including Alexemia in Soul Cradle: Sekai wo Kurau Mono and narration for the game Jitsuwa Kaidan "Mimibukuro". Her work in Japanese dubbing of foreign productions is also a significant part of her career, with credits including the role of Patricia Fernandez in the Colombian soap opera Yo Soy Betty La Fea, additional voices for the live-action film Thunderbirds, and the voice of Maronda in the Power Rangers franchise.