The Nihonkai evergreen forests ecoregion (WWF ID: PA0427) covers a thin strip of land on the western coast (facing the Sea of Japan) of the island of Honshu in Japan.

It is bounded on the east by the Nihonkai montane deciduous forests ecoregion.

[1][2] The coastal strips extends for most of the length of the island, encompassing bays, inlets, rocky coasts and caves.

This climate is characterized by large seasonal temperature differentials.

[3], The dominant trees in this region is Castanopsis sieboldii, Picea jezoensis, Pinus thunbergii, Pinus pumila, Prunus nipponica, Cryptomeria japonica, Sciadopitys verticillata, Salix pierotii, Camphora officinarum, Cercidiphyllum japonicum, Fagus crenata, Carpinus laxiflora, Tilia amurensis, Larix gmelinii, Larix sibirica, Larix × czekanowskii, Betula dahurica, Betula pendula, Pinus koraiensis, Pinus sibirica, Pinus sylvestris, Picea obovata, Abies sibirica, Quercus acutissima, Quercus mongolica, Ginkgo biloba, Prunus serrulata, Prunus padus, Tilia amurensis, Salix babylonica, Acer palmatum, Populus tremula, Ulmus davidiana, Ulmus pumila, Haloxylon ammodendron, Elaeagnus angustifolia, Tamarix ramosissima, Podocarpus macrophyllus, and Prunus sibirica.