Fanny Lucía Martínez Buenaventura (born 8 February 1973), better known professionally as Fanny Lú, is a Colombian singer-songwriter and actress from Santiago de Cali, Colombia. She studied at the University of the Andes and received a degree in industrial engineering. She is the mother of two children, Mateo and Valentina, and is currently divorced. She signed with Universal Music Latino record label.

Her first job in the entertainment industry was in Colombia, as hostess to a music magazine called "Siempre Música". She then moved on to radio voice in the principal radio stations from her country. However, she wasn't recognized until 1998, when she made part of the cast from the Colombian soap opera Perro Amor.