Nephrolithiasis is a common disease. Acute renal colic due to migration of stone is a frequent cause of admission in emergencies departements (ED). Diagnostic procedures in such centers are already well codified. This article discuss the diagnostic management and particularly the question of the radiological evaluation in patients presenting with renal colic to the general practitioner (GP). Because of the high risk of recurence and in order to identify patients with high stone burden, every patient presenting a first episode of renal colic should undergo radiological investigation. Considering sensitivity, irradiation rate, cost and diagnostic information, we recommend the (low-doses CT-SCAN as exam of choice for initial radiological evaluation of patient with renal colic.