To investigate the effects of three cultivation methods(ridge cultivation, box ditch cultivation, flat cultivation(conventional)) on rice root characteristics, soil fertility and rice yield, we performed a field plot experiment in Liuyang City, Hunan Province by use of Zhongjiazao 17(early rice season) and Taiyou 390(late rice season). The results showed that compared with flat cultivation, ridge cultivation had more of the total root length and root surface area from booting stage to full heading stage of late rice season, which were 49.43%, 46.13% and 52.14%, 36.90% respectively. The total root length and root surface area at the peak tillering stage in the late rice season were fewer by 33.75% and 31.39%, respectively. The ridge cultivation increased root bleeding volume from booting stage to full heading stage in early and late seasons by 73.31%, 101.14% and 92.81%, 52.22% respectively. Meanwhile, compared with flat cultivation, the ridge cultivation significantly increased soil urease activity in early and late rice fields as well as the content of organic carbon in 0-20 cm soil layer in early and late season. The box cultivation significantly decreased the content of organic carbon in >5-10 cm soil layer in late season with no significant difference in total nitrogen content in 0-10cm soil layer of rice fields in early and late rice seasons. In >10-20 cm soil layer of late rice season, flat cultivation owned the highest total nitrogen content, which was significantly higher than that in other treatments(47.22%-55.88%). In addition, ridge culture could increase the ratio of carbon and nitrogen in the >5-20 cm soil layer of late rice season and the effective panicles and total grains per panicle in early and late rice seasons, while the box cultivation increased the total grains per panicle in early and late rice seasons resulting the increased yield. In conclusion, the ridge cultivation was in favor of increasing the soil fertility of rice fields and the yield of double cropping rice.