Increased attention has been paid to the influence of environmental factors caused by coal mining subsidence on plant physiology. Stomatal conductance, transpiration and rate of photosynthesis are factors sensitive to the environment, therefore it is important to study of the change in stomatal conductance, transpiration, and photosynthetic rate to reveal the change of natural environment in the mining area. Investigation of the changes in stomatal conductance, transpiration, and photosynthetic rate under the condition of coal mining subsidence is a key step to explore the effects of coal mining on water transpiration and CO₂ assimilation rate. It is concluded that the relationships between stomatal conductance, transpiration, and photosynthetic rate and environmental factors in coal mining subsidence areas are the basis of the relationship between energy and water exchange under the influence of coal mining subsidence. However, the responses of stomatal conductance, transpiration, and photosynthetic rate to the change in soil water content are not clear in coal mining subsidence areas. The 52302 working face of the Daliuta mining area was selected as the experimental site, with Caragana korshinskii as the research object. Stomatal conductance, transpiration and rate of photosynthesis in C. korshinskii leaves and soil water content were monitored in a coal mining subsidence area and a non-collapse area. The characteristics of the responses of stomatal conductance, transpiration, and photosynthetic rates of C. korshinskii leaves to soil water content were analyzed. The results show that:(1) Coal mining resulted in surface cracking, soil structure damage and diving depth reduction. Soil water content was lower than that in the early stage of the subsidence. Compared with the control area, the soil moisture contents of the hard ground and the aeolian sandy land subsidence area were decreased by 18.61% and 21.12%, respectively. (2) The stomatal conductance, transpiration, and photosynthetic rate of C. korshinskii leaves were positively correlated with soil water content. Subsidence of coal mining area increased the loss of surface water and intensified the degree of soil water stress. In order to reduce transpiration caused by water loss, C. korshinskii leaf stomatal resistance increased, stomatal conductance decreased, and CO₂ supply for photosynthesis was hindered, which led to the reduced C. korshinskii leaf photosynthetic and transpiration rates.