The relationships of Syrmaticus to Phasianus remain uncertain and opinions differ whether they are separate genera or congeneric.We examined the relationships of Syrmaticus to Phasianus, Lophura, and Catreus by means of Cyt-b gene array comparisons.As a result, we found that each of the following groups forms a cluster, (1) Syrmaticus soemmerringii, (2) Syrmaticus reevesii, (3) Syrmaticus ellioti, S.humiae, S.mikado and (4) Lophura erythrophthalma, Catreus wallichii and Phasianus versicolor. There was 10.81% difference between cluster(3), Elliot's, Huume's and Mikado Pheasant, and cluster(4), Crestless Fireback, Cheer and Green Pheasant (Phasiunus).The Cheery Pheasant, the taxonomic position of which has been debated, was included in the Green Pheasant cluster in our experimental data and hence considered to be more closely related to Phasianus than to Syrmaticus.