Climate change will greatly increase the vulnerability of one-third of all Maine species assessed. Of 442 ranked species, 37% were ranked highly vulnerable to climate change and another 38% were ranked moderately vulnerable. Fifty percent of SGCN mammals and state-listed Threatened or Endangered plant species were ranked highly vulnerable to climate change (Table 1). Over 50% of plant and bird species reviewed were highly vulnerable to climate change. All species groups had many species that were ranked highly vulnerable to climate change. This includes iconic species such as the common loon (Gavia immer), eastern moose (Alces alces americana), Atlantic puffin (Fratercula arctica), and landlocked salmon (Salmo salar Sebago). Twelve non-listed fungi and lichen species were added to the assessment and 11 were ranked as highly vulnerable. More than 50% of the Species of Greatest Conservation Need found in three Comprehensive Wildlife Conservation Strategy, Key Habitats (Alpine, Montane Forest, and Peatlands) ranked highly vulnerable to climate change. Most species in early successional and human-affected ecosystems (e.g., agriculture) had low vulnerability. Climate change poses a large threat to 10% of Maine’s habitats. The most vulnerable habitats are alpine and montane systems, peatlands, northern river shores, spruce flats, and cedar lowlands. Together, moderately and highly vulnerable habitats cover more than 33% of Maine. Applying the following four actions will greatly reduce threats posed by climate change to Maine’s wildlife: (1) update Maine’s Comprehensive Wildlife Conservation Strategy, and SGCN list, considering climate change vulnerability; (2) apply innovative conservation strategies aimed at reducing new threats; (3) continue to apply existing conservation strategies as they play a key role in climate change adaptation; and (4) apply regional strategies in cooperation with neighboring states and provinces.