The carbon balance of Arctic ecosystems is particularly sensitive to global environmental change. Leaf respiration (R), a temperature-dependent key process in determining the carbon balance, is not well-understood in Arctic plants. The potential for plants to acclimate to warmer conditions could strongly impact future global carbon balance. Two key unanswered questions are (1) whether short-term temperature responses can predict long-term respiratory responses to growth in elevated temperatures and (2) to what extent the constant daylight conditions of the Arctic growing season inhibit leaf respiration. In two dominant Arctic species E riophorum vaginatum (tussock grass) and B etula nana (woody shrub), we assessed the extent of respiratory inhibition in the light (R L/R D), respiratory response to short-term temperature change, and respiratory acclimation to long-term warming treatments. We found that R of both species is strongly inhibited by light (averaging 35% across all measurement temperatures). In E . vaginatum both R L and R D acclimated to the long-term warming treatment, reducing the magnitude of respiratory response relative to the short-term response to temperature increase. In B . nana, both R L and R D responded to short-term temperature increase but showed no acclimation to the long-term warming. The ability to predict plant respiratory response to global warming with short-term temperature responses will depend on species-specific acclimation potential and the differential response of R L and R D to temperature. With projected woody shrub encroachment in Arctic tundra and continued warming, changing species dominance between these two functional groups, may impact ecosystem respiratory response and carbon balance.