Nowadays, treatment of meniscal tears is conservative with removal only of the broken part of meniscus. For this reason, before arthroscopy, the orthopaedic surgeon needs for an accurate preoperative diagnosis that could be obtained with computed tomography (CT) and magnetic resonance (MR). Our purpose is to value the actual role of CT and MR in diagnosis of meniscal tears. We retrospectively evaluated CT and MR images of 128 patients (average age 32 years) who then underwent arthroscopy. On the basis of our findings CT and MR have been shown to be very accurate to detect meniscal tears, even if with both methodics false positives and false negatives are possible. Nevertheless, MR is able to give high resolution multiplanar images without using ionising radiations and is preferable because of its high accuracy in recognising associated lesions of ligaments or articular cartilage.