At the age of thirteen, Ueto made her acting debut in the 1999 thriller "Satsujinsha: Killer of Paraiso". In 2001, Ueto appeared in the sixth season of the TBS drama "3-nen B-gumi Kinpachi-sensei". Her portrayal of a high school student with gender dysphoria garnered critical acclaim and led to several leading roles and advertising endorsements, establishing Ueto as one of Japan's most recognizable faces. Since 2004, Ueto has held the annual title of CM Queen five times. Ueto has won two Television Drama Academy Awards – one for Best Actress for her performance in the sports drama series "Ace o Nerae!" (2004) and one for Best Supporting Actress for her role in the human drama "Nagareboshi" (2010). She subsequently starred in the remake of "Attention Please" (2006), the banking drama "Hanzawa Naoki" (2013) and "Hirugao: Love Affairs in the Afternoon" (2014).