Five kinds of drainage materials were chosen such as gravel, ceramsite, glass pumice, HDPE and PVC drainage boards, to establish a simulation test bed of extensive green roof with Sedum lineare Thunb (indoor natural state). The temperature and moisture of the soil, as well as the temperature and relative humidity of the air at the bottom of soil layer by different material treatments were measured. The results showed that:The soil moisture was affected significantly by different drainage materials during the less rain season, but the difference was not significant during the rainy season. In drought month, four kinds of drainage materials with water retention performance such as ceramsite, glass pumice, HDPE and PVC drainage boards, had obvious drought resistance advantage compared to gravel treatment, and the average soil moisture was increased by about 35%. However, the size of the water retention of these four materials had no significant effect on the soil moisture among the treatments. Other than that the drainage performance of the materials had a significant effect on the soil moisture. Early after the rain, the soil moisture of the HDPE drainage board with larger water flux was significantly smaller than other material treatments. Soil temperature and soil air temperature were not affected by water retention performance of the materials. It is indicated that the changes of soil hygro-thermal environment on the extensive green roof are not completely determined by the water retention performance of the materials. Meanwhile, the extensive green roof has both heat-insulating(all year daytime) and heat-preservation(winter nighttime) effects, and its thermal performance has seasonal and intraday differences.