Abstract: In order to predict the farmland ecological system, CO2, N2O and CH4 emissions on global warming response and the influence of temperature on the daily dynamics of greenhouse gas emission. Daily dynamics of CO2, N2O and CH4 flux from farmland ecosystem in spring wheat field at mature stage were measured by static chamber-gas chromatographic techniques under conventional tillage (T) and conservation tillage (NTS) in dry land of loess plateau. The results showed that: fields were sources of atmospheric CO2 and N2O and the sink of atmospheric CH4 under two tillage treatments. Daily dynamics of CO2, N2O and CH4 flux changed remarkably. CO2 emission flux under conventional tillage was obvious higher than that under conservation tillage, the maximal emission flux of CO2 appeared at 12:00 pm, and the minimum emission appeared at 0:00 am. The maximal emission flux of N2O appeared at 16:00 pm and the minimum emission appeared at 0:00 am. Conservation tillage treatment could increase N2O emission. The maximal absorption flux of CH4 appeared at 14:00 pm under two tillage treatments, the minimum absorption appeared at 22:00 pm under conservation tillage, but the minimum absorption appeared at 2:00 am under conventional tillage treatments. Conservation tillage could increase CH4 absorption. The land surface temperature and soil temperature at the depth of 5 cm were significantly related to CO2 emission flux, and that there was a significant exponential correlation between CO2 flux and the soil temperature.conservation tillage, the maximal emission flux of CO2 appeared at 12:00 p.m, and the minimum emission appeared at 0:00 a.m. The maximal emission flux of N2O appeared at 16:00 p.m and the minimum emission appeared at 0:00 a.m. Conservation tillage treatment can increase N2O emission. The maximal absorption flux of CH4 appeared at 14:00 p.m under two tillage treatments, the minimum absorption appeared at 22:00 p.m under conservation tillage, but the minimum absorption appeared at 2:00 a.m under conventional tillage treatments. Conservation tillage can increase CH4 absorption. The land surface temperature and soil temperature at the depth of 5cm were significantly related to CO2 emission flux, and that there was a significant exponential correlation between CO2 flux and the soil temperature.