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Soil carbon dioxide (CO 2 ) emission from agricultural areas is a complex phenomenon with high temporal and spatial variability. Tillage practices can affect drivers of CO 2 production and therefore influence emissions by soils. However, the impact of tillage management on CO 2 emissions from soil is uncertain due to specific climate and soil characteristics. A field experiment was initiated in 1992 in Shanxi, China including the no-tillage plots with straw mulching (NT) and conventional-tillage (CT) treatment. In 2012, another treatment (NT0) was conducted during which the straw was not returned to the plots when the winter wheat harvested. The CO 2 emissions, soil temperatures and soil moisture content were measured during the fallow and wheat-growing periods from 2013 to 2015. Results showed that the rate of CO 2 emissions was significantly higher immediately after tillage operation in the CT treatment. The annual CO 2 emission rate in the NT treatment was significantly greater than that in the CT and NT0 treatments ( P < 0.05). For different season, the highest CO 2 emissions rate occurred in summer (0.20 g CO 2 -C m − 2 h − 1 ) while the lowest CO 2 emissions rate occurred in winter (0.04 g CO 2 -C m − 2 h − 1 ). These rates were only positively correlated with the soil temperatures ( P < 0.05) and not significantly correlated with the soil moisture contents. Our results indicated that NT farming practices demonstrated increases CO 2 emissions from soil compared with the CT and NT0 treatments under dryland cropping system. [ABSTRACT FROM AUTHOR]