Xylella fastidiosa is plant-pathogenic bacterium transmitted by leafhoppers (Hemiptera: Cicadellidae) in the subfamily Cicadellinae, commonly known as sharpshooters. In the United States and Mexico, a particular strain of this pathogen causes Pierce's disease (PD) in grapes. PD has not been reported in Brazil, although grape is a major crop in the State of Rio Grande do Sul (RS). In this study, we conducted a survey of Cicadellinae leafhoppers by yellow sticky traps in grape orchards of the region of Bento Goncalves/RS, during 09/2004-09/2006, in order to identify potential vectors of X. fastidiosa. In four different farms, we collected a total of 25 Cicadellinae species in the tribes Proconiini (715 individuals; 11 species) and Cicadellini (1,762 individuals; 14 species). Six of these species have been previously reported as vectors of a citrus strain of X. fastidiosa. The diversity and abundance of native sharpshooters found in our survey indicates a high risk of PD spread in grapes if a pathogenic strain of X. fastidiosa evolves or is introduced in the State of Rio Grande do Sul.