Born in Vila Velha, Espírito Santo, Jullie moved to São Paulo to pursue an acting career. In 1998, she appeared in television shows Xuxa Park, Gente Inocente and Criança Esperança. Jullie also landed her first starring role in Mais Uma Vez Amor, released in February 2005, interpreting the character Lia. In 2005 she began her career as a voice actress. Jullie lent her voice to many Brazilian versions of television series and films, including Blair Waldorf in Gossip Girl, Katie in Total Drama Island and Roxy in Winx Club.
Her debut album Hey!, was released on September 22, 2009, the album was influenced by singers like Lily Allen, Madonna, Alanis Morissette, and its main reference, Katy Perry, directed to a feminist position. The album was praised by the young, calling Jullie the "Brazilian Katy Perry" for her music style and way of dressing. The first single, "Alice", was released in April, and the second single, "Hey!", was released in November, 2009. In February 2010, "Tudo Pode Mudar", a cover of the popular band from the 1980s Metrô, was released for the Brazilian TV series Malhação. On August 2, 2010, Julie recorded a Brazilian version of "Wouldn't Change a Thing" entitled "Eu Não Mudaria Nada em Você" with Joe Jonas for Camp Rock 2: The Final Jam soundtrack.