The Hawaiian tropical rainforests are a tropical moist broadleaf forest ecoregion in the Hawaiian Islands. They cover an area of in the windward lowlands and montane regions of the islands. Mixed mesic forests occur at elevations of , while wet forests are found from . Moist bogs and shrublands exist on montane plateaus and depressions. This ecoregion includes one of the world's wettest places, the slopes of Mount Waialeale, which average of rainfall per year.

Coastal mesic forests

Coastal mesic forests are found on the windward slopes of the major islands from sea level to . These forests have been dominated by the native hala (Pandanus tectorius) and hau (Hibiscus tiliaceus) and naturalized (Polynesian introductions) kukui (Aleurites moluccana) and milo (Thespesia populnea) for the past 1,000–2,000 years. The Polynesian-introduced noni (Morinda citrifolia), pia (Tacca leontopetaloides), and kī (Cordyline fruticosa) are also common in this zone. Other native species include pololei (Ophioglossum concinnum),

Mixed mesic forests

Mixed mesic forests, at on the windward slopes of the large islands in addition to the summit of Mount Lānaihale on Lānai, receive of rainfall annually and thus may not be true rainforests. The forest canopy, dominated by koa (Acacia koa) and ōhia lehua (Metrosideros polymorpha), is somewhat open, but tree density is rather high. Other trees and shrubs include pāpala (Charpentiera obovata), olopua (Nestegis sandwicensis), hame (Antidesma platyphyllum), mēhame (A. pulvinatum), kōpiko (Psychotria mariniana), ōpiko (P. mauiensis), iliahi (Santalum freycinetianum), hōlei (Ochrosia spp.), poolā (Claoxylon sandwicense), kōlea lau nui (Myrsine lessertiana), kauila (Alphitonia ponderosa), nioi (Eugenia reinwardtiana), aiai (Paratrophis pendulina), and hōawa (Pittosporum spp.).

Wet forests

Wet forests generally occur from ,

Protected areas:

  • Olaa Forest in the Hawaiʻi Volcanoes National Park.

Bogs

Bogs are found in montane regions where rainfall exceeds drainage. Dominant vegetation in bogs are shrubs, sedges, and grasses. Larger shrubs and small trees grow on bog perimeters or on raised hummocks. Carex spp., Oreobolus furcatus, and Rhynchospora rugosa are common sedges, shrubs include ōhelo kau laau (Vaccinium calycinum) and ōhelo (V. dentatum), while grasses are represented by Dichanthelium spp. and Deschampsia nubigena. The ferns wāwaeiole (Lycopodiella cernua), amau (Sadleria spp.),