Whether CT or MRI is better for checking the urinary system should be determined according to the specific part of the examination, such as CT is better for kidney examination and MRI is better for prostate examination. CT is better for kidney examination because CT scanning speed is faster, it can be examined several times, density resolution is more obvious, clinically used for benign or malignant lesions of the kidney, and it is better for diagnosing kidney stones and ureteral stones. Prostate examination with magnetic resonance is better, because magnetic resonance in different windows have different imaging performance, and magnetic resonance can be very good to show the surrounding area of the prostate, can further determine the occupation of the prostate is malignant or benign. Therefore, for the urinary system examination should be based on the specific which organ is examined, according to the different circumstances to give different examination, so as not to delay the condition.