Objective To evaluate the applied value of low-dose CT urography (CTU) for the diagnosis of ureteral diseases. Methods 43 patients with ureteral diseases recruited in this study were divided into two groups. Normal-dose group: twenty of them underwent CTU with tuber voltage of 120 kv and tuber current of 350 mA. Low-dose group: the other twenty-three patients underwent CTU with 120 Kv and 100-120 mA. The Image quality scores (IQS) of both axial and reformatted images in excretory phase of ureters were assigned by two radiologists with double blind method, and the effective dose (ED) as well as the diagnostic coincidence rate were also evaluated. Results There was no statistical difference in the IQS and the diagnostic coincidence rate between the two groups(P>0.05). All images quality can meet diagnostic requirement. The average value of ED of normal-dose group was (43.20±2.05) mSv. The average value of ED of low-dose group was (12.95±1.56) mSv, reducing 70.02% the intrinsic dose compared to normal-dose group (P<0.01). Conclusion Low-dose CT urography can decrease markedly the radiation dose, and the images are satisfactory for the diagnosis of ureteral diseases.