She worked as a model starring in several TV commercials and as a dancer in SBT's Domingo Legal show before becoming an actress. Fernanda played the lead role of Betina in the 2005 season of Malhação working with actor Thiago Rodrigues. After leaving Malhação, she played an art student character named Nanda in the 2006 Rede Globo telenovela Páginas da Vida. This was her second time as Thiago Rodrigues' love interest. Fernanda Vasconcellos won the Best Newcomer Actress Award for this performance. Next, she played the lead role of Clara in the 2007 telenovela Desejo Proibido. Set in a fictional 1930s city located in Minas Gerais state, her romantic interest was a character played by Murilo Rosa.
In the 2010 telenovela Tempos Modernos, Vasconcellos again played a character romantically involved opposite actor Thiago Rodrigues, in what would be the third time in her career. She played the lead as Nelinha. Vasconcellos plays the lead role in the 2011 Rede Globo telenovela A Vida da Gente as a tennis player named Ana Fonseca. She plays one of the lead roles in the 2013 Rede Globo telenovela Sangue Bom as Malu, a college student rejected by her famous mother.