Carbon dioxide flux in soil profiles of arid areas in north temperate regions of China was studied using an open-sample pole method. The results showed that CO2 flux increased with soil depth up to 60 cm, then decreased. The average CO2 flux at 0-70 cm depth was 660 μmol/(m2·h), with forest soils releasing more CO2 than grassland soils. Different soil types had varying CO2 flux, with turning points in the flux-depth curve related to soil structure and root distribution. Soil CO2 flux was higher during the growing season. It was found that careful treatment of soils when breaking the ground can reduce the release of CO2 into the atmosphere.