[Objective] To accurately understand the effects of coal mining on vulnerable ecological environment.[Methods] Soil physical properties and soil crust in current and three years later after ultra wide fully-mechanized coal mining in Mu Us desert were analyzed with sample plot survey and indoor element content analysis.[Results] The soil physical properties in fracture zone affected by coal mining were stronger than mined-out area

but the soil repairing ability in mined-out area was better than fracture zone

and coal mining effects on soil physical properties still exist after three years later. The soil temperatures of each sampling point not only have differences with the control group

but also have differences in spatial and temporal span. Soil bulk density

porosity and moisture content in twenty centimeters were negatively correlated with soil temperatures

and the soil moisture content had a significant correlation with soil temperature. Thickness and coverage of soil crust were affected by coal mining

and soil crust moisture content and water holding ability didn't return to the level before coal mining within three years.[Conclusion] The coal mining with ultra wide fully-mechanized cause damage on soil physical properties and soil crust

and the soil will be self-restored in the absence of human disturbance

but there is a certain difference between the effect of three years restoration and control.