Yu Aoi (蒼井 優, Aoi Yū; born August 17, 1985) is a Japanese actress and model. She made her film debut as Shiori Tsuda in Shunji Iwai's 2001 film All About Lily Chou-Chou. She subsequently portrayed Tetsuko Arisugawa in Hana and Alice (2004), also directed by Iwai, Kimiko Tanigawa in the hula dancing film Hula Girls and Hagumi Hanamoto in the 2006 live-action adaptation of the Honey and Clover manga series.

She has won numerous awards for her performances on screen, including the Japan Academy Prize and Kinema Junpo Awards for best supporting actress in 2007 for Hula Girls and Rookie of the Year for continued performances in the field of Films in Media and Fine Arts by the Ministry of Education, Culture, Sports, Science and Technology of Japan in 2009.

Aoi was born on August 17, 1985, in Fukuoka Prefecture, Japan. She moved to Tokyo in junior high school and lived in Kasai, Edogawa ward.

Yu Aoi made her stage debut as Polly in the 1999 rendition of Annie, followed by her appearance as a regular on TV Tokyo's Oha Suta (The Super Kids Station) in 2000. A year later, she debuted in Shunji Iwai's All About Lily Chou-Chou playing Shiori Tsuda alongside Hayato Ichihara, Shugo Oshinari, Miwako Ichikawa, and Ayumi Ito. Aoi would later work in Ao to Shiro de Mizuiro and Gaichu with friend Aoi Miyazaki. With her first roles on the small and big screen came TV commercials and endorsements for Sony, Yamaha, DoCoMo, Toshiba and Coca-Cola.

In 2003, commemorating the 30th anniversary of Kit Kat in Japan, Shunji Iwai shot a series of short films starring Yu Aoi and Anne Suzuki, which later was expanded into the feature film called Hana & Alice, which earned Aoi the Best Actress award at the Japanese Professional Movie Award.

In 2005, Aoi played her first lead on the big screen in Letters from Kanai Nirai, which was sold in Korea with the alternate title of Aoi Yu's Letter due to her popularity. She also had supporting roles in the Satoshi Miki film Turtles Swim Faster than Expected starring Juri Ueno, and Yamato with Shido Nakamura and Kenichi Matsuyama. This supporting role would earn her one of her double-nomination as Best Supporting Actress at the 2007 Japanese Academy Award. She won against herself for her work as Kimiko Tanikawa in the Japanese hit Hula Girls, which was sent to the Academy Awards as the Japanese official selection that year.

To this date, her role as the hula dancing girl from small town Iwaki remains her most successful role yet, earning her a dozen awards as Best Actress and Best Supporting Actress, alongside her other smaller roles that year as Hagu in Honey & Clover, and Kana Sato in the Shunji-Iwai-produced and Nirai-Kanai-directed Rainbow Song. Aoi also lent her voice to play Shiro in the animated film Tekkon Kinkreet, the adaptation to the Taiyō Matsumoto manga, Black and White, directed by Michael Arias.

During these years, she made commercials for Nintendo, Canon, Shiseido Cosmetics, Shueisha Publishing, Kirin Beverage and continued endorsing DoCoMo. Aoi also released two photobooks with Yoko Takahashi as photographer, and distributed by Rockin'on: Travel Sand in 2005 and Dandelion in 2007.