Ellen Joyce Loo

• Name — Ellen Joyce Loo • Born — 27 March 1986 • Birthplace — Toronto, Ontario, Canada • Died — 5 August 2018 • Place of death — Happy Valley, Victoria City, Hong Kong (special administrative region of China) • Native Name — 盧凱彤 • Occupation — * Musician • singer-songwriter • record producer • Education — Secondary 5, St. Paul's Convent School • Years Active — 2002–2018 Ellen Joyce Loo Hoi Tung (27 March 1986 – 5 August 2018) was a Hong Kong musician, singer-songwriter and record producer. She was the guitarist, backing vocalist and a co-founder of the folk-pop rock group at17.

Loo was born in Toronto, Canada, on March 27, 1986. At age 4, she moved to Hong Kong. She learned classical guitar from her father at the age of nine. At age 14, she and her older brother, P. J. Loo, entered the musical competition "Original Music 2000" (原音2000), which was held by Tom Lee Music in Hong Kong. They won third prize in the competition.

Loo was diagnosed with bipolar disorder in 2013, and made her first public statement regarding the disorder in April 2015. She came out as a lesbian at the Golden Melody Awards in Taiwan in 2017. She married Taiwanese cinematographer Fisher Yu in 2016. The couple registered their marriage in Canada.

Loo died after falling from her apartment building in Happy Valley, Hong Kong, on 5 August 2018, at the age of 32. The case was classified as suicide by police after checking CCTV footage of the building. No suicide note was found.