Niigaki Risa, born October 20, 1988 in Kanagawa, Japan, is a Japanese pop singer under Hello! Project. She is a 5th generation member and the current leader of the Japanese pop group Morning Musume and was a member of the group Tanpopo and the leader of Athena & Robikerottsu, as well as participating in the shuffle units Happy 7, 7AIR, ZYX and H.P. All Stars. She was also a member of the Morning Musume splinter group, Morning Musume Sakura Gumi. She joined Morning Musume in 2001 along with Takahashi Ai, Konno Asami and Ogawa Makoto. Niigaki was the sub-leader of Morning Musume, inheriting the title from the the former leader Takahashi Ai and was sub-leader until Takahashi's graduation. As of 2009, she was the longest serving sub-leader, and is currently the longest serving Morning Musume member. Niigaki is also the current leader of Hello! Project. On January 2nd, it was announced that Niigaki Risa will graduate from their next Spring Tour 2012 "Ultra Smart".

In early 2007, Niigaki was chosen to be a member of Morning Musume Tanjou 10nen Kinentai along with Iida Kaori, Abe Natsumi, Goto Maki and Kusumi Koharu - a unit created to celebrate Morning Musume's 10th anniversary. Their first single, "Bokura ga Ikiru MY ASIA", was released on January 24, 2007. On June 1, 2007, following then-leader Fujimoto Miki's resignation from Morning Musume, Takahashi Ai replaced Fujimoto as leader, while Niigaki took Takahashi's place as sub-leader.

On January 2, 2012 it was announced that Niigaki will graduate from Morning Musume and Hello! Project on the last day of Morning Musume 2012 Spring Concert Tour that is May 18, 2012.
Morning Musume leadership will be passed on to Michishige Sayumi and Tanaka Reina will be sub-leader. Niigaki will pass on the leadership of Hello! Project to Shimizu Saki from Berryz Koubou.

She began dating actor Kotani Yoshikazu after starring together in the stage play Absolute Boyfriend in 2013. They held their marriage ceremony on July 11, 2016. On January 6, 2018, both announced on their blogs that they were filing for divorce, citing they were growing apart.

On June 30, 2022 she announced that she has married YouTube cinematographer Yamaguchi Yasutake.
On September 10, 2022 she announced that she would resume her singing career. Her mini album "NIIGAKI RISA1" will be digitally released on September 16, 2022.

(Source: Hello! Project Wiki) Edit Biography