Abstract:A series of tests were carried out by means of PF-type SWCC device for SWCCs for remodelled un- saturated coal soil specimens at different initial dry density in this study. Based on test results, the influence of initial dry density on unsaturated coal soil soil water characteristic curve were studied through analyzing the VG curve model. The three times of drying-wetting cycles tests for a specimen at certain initial density were also carried out. The research results show that the dry density has a great influence on the soil-water characteristic curves of coal-bearing soil. Specimens with higher dry density generally have lower saturated content, higher water-losing speed, and better water-holding capacity. The drying-wetting cycles leads to structure change and big pore increase in soil, and water-holding capacity of coal soil can also be reduced. The effect of the 1st dry- ing-wetting cycle on coal soil SWCCs is most obvious. The SWCC of the coal soil is basically stable after the third wet-dry cycle.