[Objective] The effects of water storage irrigation and seasonal freezing and thawing on soil respiration were determined in order to improve the utilization efficiency of irrigation water resources, and save irrigation water resources at Shiyang River watershed of Gansu Province in extremely arid regions in China.[Methods] The LI-8100 automatic soil carbon flux measurement system was used to observe and analyze soil respiration rates. Treatments were divided into irrigation and non-irrigated treatments according to the low irrigation quota of 1 199.4 m³/hm². The freeze-thaw cycle was divided into three time periods:freezing period, freeze-thaw period, and thawing period.[Results] Under the effects of seasonal freeze-thaw cycles, soil respiration rate and soil carbon emissions of farmland ecosystems increased and the carbon cycle of farmland ecosystems was changed, resulting in increased crop growth and food production. Soil respiration rates responded differently to moisture and temperature under different land use patterns. During the entire process, soil respiration rate was greater during the thawing period than that of the freezing period and the freeze-thaw period. The soil CO₂ in the three periods of freezing, freeze-thaw, and thawing were all shown to be sources, but were all converted from sources to sinks at very low night temperature.[Conclusion] Water storage irrigation regulated the process of soil respiration throughout the freezing and thawing period and changed the carbon cycle of farmland ecosystems in extremely arid regions. Under the superimposed action of moisture and seasonal freeze-thaw, the soil respiration rate of storage irrigation plots fluctuated more drastically with temperature than the soil respiration rate of non-storage plots, and this result was consistent with the change trend of temperature, indicating that moisture aggravates soil respiration fluctuations with temperature.