Soil moisture content is an important factor affecting vegetation growth in semi⁃arid areas. The study on effects of coal mining on soil moisture dynamics may help reestablish vegetation in the mining area. Profile soil moisture probes were used to monitor changes in soil moisture content ( SMC) in the 10 to 100 cm soil layer of the compression area located at the 52303 working face of the Daliuta coal mine before and after the mining operation. Analysis of the monitoring data shows that before the mining operation, SMC remained quite stable and didn′t change much with temperature. In the initial period of the coaling operation SMC changed, but the change was not significant and lagged temporally behind the process of mining. The time lag reached 4-5 days, that is to say, the change in SMC became apparent 4 to 5 days later after the mining operation reached right beneath the monitoring site. Then subsidence began to develop till maximum. During the course it disturbed the soil mass, causing changes in SMC, which rose first and then fell. The disturbance of mining to SMC waned gradually with soil depth in the soil profile from top to bottom. The disturbance of the soil mass caused by sub⁃sidence also led to decrease in soil particle size, increase in bulk density and decline of void ratio, thus enhancing the wa⁃ter holding capacity of the soil mass, which explains why SMC rises temporarily in the initial period of the mining opera⁃tion. Meanwhile the occurrence of ground fissures and reduced water supply from rainfall are the two major causes that low⁃er SMC in the late period of the operation.%土壤含水量是影响干旱区植被生长的一个重要因素，研究由于煤矿开采引起的土壤水时序变化有利于矿区植被的重建。以大柳塔矿井52303工作面为例，采用剖面水分速测仪对开采前后压缩区10～100 cm深处土壤含水量的变化进行监测。通过对监测结果的分析发现，未受采煤影响时，土壤含水量较平稳，不随温度变化而改变；受采煤影响初期，土壤含水量变化不明显，存在滞后性，滞后时间为地下开采到达测点正下方后4～5d；之后，在测点达到最大沉降量过程中发现，下沉对土体的扰动作用导致土壤含水量出现先上升后下降现象，且地下开采对土壤水扰动程度由浅至深逐渐减弱。沉陷引起的土体扰动导致土壤粒径减小，容重增加，孔隙比降低，使得土壤持水能力增强，这是导致在受开采干扰初期（04－03—04－10）土壤含水量短暂上升的重要原因，而裂缝产生以及雨水补给能力的降低是导致后期土壤含水量降低的主要原因。
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