As the climate changes and sustainable development of tourism receives more and more attention from the world, the development of low carbon tourism is increasingly highlighting its importance on the sustainable development of tourism. Forest park, a tourism resource with biodiversity of the natural ecosystem, plays an important role in the maintenance of stability on the terrestrial ecosystem. In this paper, an index system for evaluation on the low -carbon tourism of national forest park was established, which used AHP and Delphi method to ascertain the index weight. Then, taking Jiadengyu National Forest Park as the example for practical study, it concluded that the low-carbon development level of the Jiadengyu National Forest Park was 0.656. At this development stage, we should put emphasis on increasing the low carbon propaganda and encouragement on tourists and tourism enterprises so as to establish a better low-carbon tourism management mechanism.