Rectal endometriosis represents one of the most severe forms of deep endometriosis. Radiologists are tasked with optimizing imaging to ensure accurate detection and then providing a detailed assessment of the extent of rectal involvement. Transvaginal ultrasonography is currently considered the first-line technique for initial diagnosis. MRI is recognized as the best imaging modality, offering a comprehensive roadmap, especially in surgical decision-making. Managing rectal endometriosis is complex, and multidisciplinary team discussion evaluating the risk–benefit balance of options provides the optimal personalized treatment, such as hormonal therapies or surgical approaches. When surgery is indicated, the success of surgical intervention and the choice of surgical technique—such as partial or complete discoid resection or segmental resection—depend on the accurate interpretation of imaging findings. This allows for informed patient consent and facilitates planning for colorectal involvement when needed. Critical key imaging factors include the exact location of the lesion; the lesion’s distance from the anal verge; the size, depth, and circumferential extent of rectal involvement; any associated deep endometriotic lesions; and the lesion count.