Somatic chromosomes (2n=26) of Araucaria araucana, Araucariaceae were observed for the first time by the fluorescent banding method using chromomycin A₃ (CMA) and 4′,6-diamidino-2-phenylindole (DAPI). The karyotype was composed of nine pairs of long metacentric chromosomes and four short chromosomes and was similar to previous works. Large and thick CMA-bands appeared at the proximal region or secondary constriction of two long metacentric chromosomes. Several weak DAPI-bands appeared at the interstitial and/or centromeric regions on some chromosomes. Most chromosome pairs were identified by chromosome shape and fluorescent banding pattern.