Introduction: It is possible to sustain an injury to the anterior cruciate ligament that can damage the cartilage and meniscus, as well as cause arthritis. MRI imaging signs can be used to diagnose knee joint ACL injuries accurately and feasibly in this study. Between Jan 2019 and October 2019, we recruited 80 patients admitted to our hospital with highly suspected anterior cruciate ligament injuries. MRI and arthroscopy findings for ACL injuries were compared, as well as the value of MRI to diagnose ACL injury. Of the 80 participants, 65 (28 with complete tears, 37 with partial tears) had ACL injuries. There was individual association between ACL injury and different MRI signs, such as continuity breakdown, thickening and edema, and abnormal gait (P0.05). On the scale of 1 to 8, all eight indirect MRI signs were very specific and low sensitive, but the lateral collateral ligament monolayer display, the Notch sign, meniscus exposure signs of the posterior ankle, and the posterior cruciate ligament index were the most specific (P0.05). ACL injury is correctly diagnosed using MRI, and clinical treatment plans can be developed based on its results. Non-traumatic diagnosis of ACL injuries might best be accomplished with MRI