Abstract: Objective：To evaluate the efficacy and safety of nonenhanced CT with coronal reconstruction for the diagnosis of urolithiasis and made comparisons with intravenous urography (IVU) and enhanced CT urography (CTU). Methods：Patients whom underwent surgery for urolithiasis in Zhongshan Hospital, Fudan University from year 2014 to 2016 were analysed retrospectively, among 125 patients were selected for analysis. The criteria for patient selection include an initial treatment for upper urinary stones and concomitant examinations by ultrasound, nonenhanced CT with coronal reconstruction, and either intravenous urography (IVU) or urography (CTU). All 125 patients had ultrasound and nonenhanced CT with coronal reconstruction, while 97 of them had IVU and 43 had CTU. Regarding the site of stones, there were 61 renal calculi, 51 ureteral calculi and 13 renoureteral calculi. The examination time, radiological dose, stone detection rate, and visibility rate of the distal ureter below calculi using different imaging approaches were compared. Results：Sensitivity of stone detection using ultrasound, IVU, nonenhanced CT with coronal reconstruction and CTU was 84% (105/125), 73% (71/97), 100% (125/125), and 100% (43/43), respectively (P＜0.001). The visibility rate of distal ureter was 49% (48/97) for IVU, 84% (105/125) for nonenhanced CT with coronal reconstruction, and 88% (38/43) for CTU (P＜0.001). The examination time by IVU, nonenhanced CT and CTU was 2030 min, 2 min, and 2030 min, respectively; and the radiological dose was 37 msV, 59 msV, and 1540 msV. Conclusions：Nonenhanced CT with coronal reconstruction had higher stone detection rate compared to either ultrasound or IVU and led to lower dose of radiological exposure compared to CTU. Nonenhanced CT with coronal reconstruction could provide sufficient information for the diagnosis and treatment of urolithiasis, with the characteristics such as convenience, short time in examination, few dose of radiological exposure, and free of contrastrelated complications. 〖BP(〗It could be regarded as the priority choice for those stones requiring specific treatment and an effective approach for followup as well.