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The spatial correlation between soil water content and root distribution in non-irrigation dense-dwarf jujube plantations was analyzed in semiarid hilly loess region of China. The soil coring method was used to sample roots at different depths within the 0~1000cm soil profile under different-aged jujube plants (1, 3, 5 and 12a). The results showed that the increment of average annual root depth decreased with the increase of jujube stand age. The maximum root depth of 12-year-old jujube was 520cm and the minimum root depth was 100 cm from the tree base, which was half-way between two trees planted 2 m apart. The difference between maximum and minimum root depths of 12-year-old jujube trees was 180 cm. Lateral roots started developing intersection networks after three years of planting. Soil water fluctuation was not induced by vertical root systems of dense-dwarf jujube plants. Root depth, dry soil layer depth and annual soil water variance within top 0~200 cm soil layer increased with increase of jujube stand age. However, root-zone soil water content decreased with increase of stand age, while dry soil layer depth was slightly larger than root depth. The results can provide vital technical support for jujube cultivation especially under semiarid conditions.