Abstract: Objective:To reduce radiation dose and ensure sinus image quality in children with optimizing tube current.Materials and Methods:80 children were randomly divided into standard dose group and three low dose groups, in which tube voltage was constantly 120kV and tube current were 350mA, 235mA, 175mA, and125mA, respectively.The mean DLP and ED of each group were measured, compared with mean ED in standard dose group, and then decrease of ED in three low dose groups were calculated separately.The image quality in all groups was blindly evaluated.Results:Compared with standard dose group, ED of other three groups decreased by 23.9%, 42.7%, and 60.2%, respectively.For image quality in all groups, there were no differences found.All sinus images reached desired diagnostic quality.Conclusion:With reduced tube current of 125mA, low dose CT of sinuses in children can yield diagnostic image quality;further radiation dose are reduced about 60%.