BACKGROUND The problem of urolithiasis is on the rise, so also the complications associated with this condition. As mentioned earlier, it is increasingly important to understand calculus as the cause of pain and the complications of calculus disease. From the multitude of imaging options available, we have to choose the optimum imaging modality, which is truly cost effective. The present study is an attempt to define the most important modality for the diagnosis of calculus disease of the urinary tract. As a corollary, we are in a position to derive other statistically important parameters of the condition. We wanted to study the radiological methods namely, X-Ray KUB, USG and CT in the evaluation of renal colic. METHODS Ultrasound, CT scan and plain X-ray KUB study were done in 104 patients presenting with symptoms typical of renal colic attending the medical and surgical OPD in Santhiram medical college and general hospital. RESULTS The percentage of detection of urolithiasis by X-ray is 60.5%, USG is 71% and CT is 96.1%. CONCLUSIONS CT is superior to ultrasound and plain radiography in detecting urolithiasis.