Abstract: By using eddy covariance technique, this paper studied the CO₂  flux in a Phyllostachys edulis forest ecosystem with high-efficiency management in Zhejiang Province of China from December, 2010 to November, 2011, and analyzed the variations of net ecosystem exchange (NEE), ecosystem respiration (RE), and gross ecosystem exchange (GEE). During the study period, the monthly NEE was always negative, with the maximum (-99.33 g C·m^-2) in July and the minimum (-23.49 g C·m^-2) in November, and the seasonal change showed a bimodal shape. The average diurnal change of the monthly CO₂ flux varied greatly from -0.30 g CO₂·m^-2·s^-1(January) to -0.60 g CO₂·m^-2·s^-1(September). The NEE at the time point of positive and negative conversion had obvious seasonal characteristics. The yearly RE changed in unimodal shape, with the maximum in summer and the minimum in winter. The RE at nighttime had significant negative correlation with soil temperature. The yearly NEE, RE, and GEE were -668.40, 932.55, and -1600.95 g C·m^-2·a^-1, respectively, among which, the NEE occupied 41.8% of the GEE. As compared with other ecosystems, P. edulis forest ecosystem had a strong capability in carbon sequestration.