Both DNA genomic fragment and open reading frame (ORF) encoding a Trx h, called VvCxxS2, were isolated and cloned from grape (Vitis vinifera L.) berry tissue. The DNA genomic fragment of VvCxxS2 possesses two introns at positions identical to the Trx h genes from grape and higher plant. The exon-intron junctions obey the rule GT-AG, as in higher plant genes. The intron position analysis in the chlamydomonas reinhardtii and vertebrates Trx genes revealed that two introns of chlamydomonas and one intron from vertebrates Trx genes are located at the same positions with introns of higher plants Trxs h and f genes, strongly suggesting a common origin for green algae, higher plants Trxs h and f, and vertebrates. The intron position analysis in the Trx o genes showed that these genes have been subjected a late evolution and in contrast to Trxs h and f, contain a different pattern of evolution. The introns position in Trxs m, p, x, and y was also analyzed. These genes possess one intron between the regions encoding the transit peptide and the mature protein, and suggest a recent entry of other introns during late evolution. Totally, obtained results suggest that Trxs f, h, and o have a eukaryotic origin whereas Trxs m, x, y, and p are related to prokaryotic Trxs, indicating different patterns of evolution.