Objective The imaging findings of X?ray defecography （XRD） and magnetic resonance defecography （MRD） of patients with Solitary Rectal Ulcer syndrome （SRUS） were retrospectively analyzed to provide important information for clinical diagnosis and treatment. Methods 19 patients with SRUS confirmed by clinical， pathological and colonoscopy were included in this study. Among them， 15 patients underwent XRD and 7 patients underwent MRD， and 3 patients underwent both XRD and MRD. Data of all enrolled patients were collected and pelvic floor function was measured. Results In the results of XRD， 3 patients （20%） showed rectal intussusception. 8 patients （53.3%） showed external rectal prolapse and 2 patients （13.3%） showed moderate rectocele. In addition， there were 2 patients of puborectal muscle hypertrophy， and 1 patient of bladder prolapse and uterine prolapse， respectively. For MRD， 3 patients （42.9%） showed rectal mucosal prolapse （partial prolapse）. At 4 patients （57.1%） with rectocele， 3 patients （all female） had moderate rectocele， 1 patient had mild rectocele. 3 patients were also observed related anterior and middle compartment organ descent. 2 patients of pubulorectal muscle hypertrophy， no sigmoidocoele. Conclusion Defecography can evaluate the structural and functional abnormalities of pelvic floor in SRUS patients， such as external rectal prolapse， rectal protrusion， rectal mucosal prolapse， and rectal intussusception， which has guiding significance for the treatment of SRUS patients。