Background: Urinary stone disease is common and poses a significant health care burden in a working-age population. With recurrence rates of 50-70% at 10 years patients are likely to be subjected to repeated imaging. Computed tomog-raphy (CT) is the reference tool for the diagnosis of renal colic, This is because CT is fast, does not require intravenous ad-ministration of iodinated contrast material, has high diagnostic capabilities, provides direct information relative to the size and attenuation value of urinary stones.Its main limitation, how-ever, is the high radiation dose given to the patient, especially because urinary stone disease has a high recurrence rate. Aim of Study: The aim of this work is to investigate the diagnostic accuracy of ultra-low dose CT scans (ULDCT) for stone detection in patients with renal colic and hematuria. Patients and Methods: This Descriptive study was con-ducted on 201 patients exposed to ULD CT of the kidney, ureters, and bladder (KUB) scan with urinary stones attended Urology & Nephrology Center, Mansoura, Egypt from Sep-tember 2022 to September 2023, with colic pain and hematu-ria. Pregnant females were excluded from the study. Results: The study found that ULD CT has a high accuracy in detecting urinary tract stones that measures 1mm or larger. kidney stones have been found more common than the ureteral or urinary bladder stones. Also, ULD CT could detect the den-sity of different urinary stones giving information about their composition. Conclusion: Our study suggests that ULD CT with re-duced effective radiation dose has been excellent detector of stones 1mm or larger with accurate detection of size, site, den-sity of that stones & presence of hydroureteronephrosis. Recommendations: Performing further multicenter studies with larger sample size. Performing further prospective studies to assess the prognostic value of ULD CT in prediction of renal stones complications.