A protein is a sequence of amino acidal residue. Usually a sequence of amino acids in one protein is divided into several subsequences, which is thought to be an independent component or region. They are called motifs or domains. Zinc fingers are motifs that has a unique structure capturing a zinc ion in the core with several (usually four) amino acid residues, which are cysteines or histidines in most cases. Zinc fingers are kinds of transcription factors because they connect to the specific DNA sequence, so they are called DNA-binding proteins [2]. In this research protein data of three species are used for motif search: Oryza sativa and Arabidopsis thaliana for plant, and Drosophila melanogaster for insect. Protein data of A. thaliana and D. melanogaster is obtained from GenBank FTP site. Protein data of O. sativa is extracted as the open reading frame (ORF) from cDNA sequence, which is sequenced by Rice Full-Length cDNA Sequencing Project in National Institute of Agrobiological Sciences (NIAS), FAIS, and RIKEN. We selected 13,919 cDNA sequences and extracted 13,554 proteins as ORF’s from them [1]. These data are not yet public.