In January 2004, the Daegwallyeong Flux Measurement Station (DFMS) was instrumented with an eddy covariance system to study the net ecosystem exchange (NEE) over a temperate broadleaf deciduous forest on the Korean peninsula. As an initial study, short-term experiments involving turbulence tests, footprint analysis, and random error estimation were carried out to investigate the quality of the DFMS data for 3 days each during the summer and winter. The results indicated that the DFMS has a sufficient source area and well generated turbulence for flux measurement and that the measurements have low random error, without diurnal variation. The measured minimum and maximum CO2 fluxes were -27.3±3.0 µmol CO2 m-2 s-1 and 4.5±0.5 µmol CO2 m-2 s-1, respectively, with clear diurnal variation in summer. In winter, the CO2 flux was 1.1±0.2 µmol CO2 m-2 s-1 without variation throughout the day.