A cryptic plasmid from Xylella fastidiosa strain ATCC 35868 was cloned, sequenced, and the sequence entered into GenBank (U71220). The plasmid is 1296 nucleotides in length with 55% GC content and three open reading frames. A plasmid with sequence homology was found in only one other strain of X. fastidiosa, ATCC 35878, Searches of the GenBank reveal nucleotide sequence homology with plasmid pNKH43 from Stenotrophomonas maltophilia, and amino acid sequence homology with phage Pf3 from Pseudomonas aeruginosa, plasmid pAP12875 from Acetobacter pasteurianus, and plasmid pVT736-1 from Actinobacillus actinomycetemcomitans.