Preoperative and postoperative imaging of knee ligament injury hinges on the appropriate use of available modalities. Knowledge of injury patterns as well as the surgical significance of certain image findings enhances injury detection and supports appropriate preoperative planning. The radiologist must be familiar with the strengths and weaknesses of each modality for evaluating specific aspects of ligamentous pathology. This article focuses on preoperative and postoperative imaging of knee ligament injury. Basic topics pertaining to preoperative image modality selection and isolated injury detection are addressed. More advanced areas including ligamentous injury patterns, surgical indications, and postoperative imaging are also discussed.