The flux observation based on eddy covariance requires uniform underlying surface. However, in the actual observation, the terrain is often very complex. Especially in the area covered by forest vegetation, the spatial distribution of different vegetation types has a great influence on carbon flux observation. In this study, Kljun model and Art Footprint Tool were used to analyze the observation data of coniferous and broad-leaved mixed forest ecosystem in Fengyang Mountain, Zhejiang province in 2017. We aim to explore the flux source area changes of the vorticity related system in the region under different seasons and atmospheric stability conditions. The results showed that the northeast wind (0-90°) and the southwest wind (180-270°) prevailed in the study area through 2017 due to the influence of terrain; therefore, the source area distribution of flux was mainly in the northeast and southwest directions. When the flux contribution rate reached 90%, the length of the flux footprint was less than 7000 m. When the flux contribution rate was 80%, the source area length was less than 3000 m. The source areas were larger, when atmosphere stability conditions were more stable. In the distribution range of the source area, there are mainly coniferous and broad-leaved mixed forest, but also a small number of monoculture forests such as Cunninghamia lanceolata, Cryptomeria fortunei and Phyllostachys pubescens. The contribution of the source area from the largest to the smallest is coniferous and broad-leaved mixed forest, broad-leaved forest, Cunninghamia lanceolata, Phyllostachys pubescens, Cryptomeria fortunei, Pine forest.