The Hokkaidō deciduous forests ecoregion (WWF ID: PA0423) covers the northern and southern coasts of the island of Hokkaido, the northernmost of the main islands of Japan.

[1] The west and northern coasts face the colder Sea of Okhotsk.

This climate is characterized by large seasonal temperature differentials and a warm summer (at least four months averaging over 10 °C (50 °F), but no month averaging over 22 °C (72 °F).

[1] The main underbrush is Sasa, a form of dwarf bamboo.

The ecoregion is generally too cold to support the Japanese beech that is common on Honshu to the south.