Abstract: To explore the effect of regulated deficit irrigation on root growth of super rice at the booting stage, a pot experiment method was performed on super rice placed in a translucent and ventilated greenhouse. The soil moisture contents were measured by using a soil moisture meter, different degrees of regulated deficit irrigation treatments were conducted on super rice at the booting stage based on soil moisture. The degrees of regulated deficit were labelled as Group A, B and C based on their rates against field moisture capacity, respectively at 80%-70%, 70%-60% and 60%-50%, to be compared with a control group CK as flood irrigation. Regulated deficit irrigation facilitates the root growth of super rice at the booting stage, enabling the root-shoot ratio to be significantly higher than that of full irrigation. A measurement of root activity on different treatment groups indicates that root activities of groups undergoing regulated deficit irrigation treatment are significantly higher than those of the full irrigation group, with treatment group B presenting the highest activity. The results of root scanning analysis indicate that a variety of root characteristic indicators of Group A and B are higher than those of Group C, while all indicators of the three treatment groups are higher than those of Group CK. The regulated deficit treatment on super rice at the booting stage is able to reduce the volume of water for irrigation effectively, and achieve optimal effects on root growth when water deficit amounts to 60% to 70% of the field moisture capacity.