Objective To investigate the value of MRI on the perianal muscles developmental situation and associated malformations in congenital anorectal malformation.Methods The MRI features of 37 cases with congenital anorectal malformation were analyzed retrospectively.All of them were performed pelvic MRI,and 28 cases were underwent lumbosacral MRI additionally.Results Of the 37 cases,there were 9 cases with muscle belly slim and 6 cases with bilateral asymmetry of the levator ani muscle;12 cases with muscle belly slim,5 cases with bilateral asymmetry and 6 cases with irregular shape of anal sphincter.There was 1 case of ectopic kidney and fused kidney,8 cases of sacrum and coccyx vertebra deformation,4 cases of lipoma of filum terminale,3 cases of low cone,1 case of tethered cord,2 cases of cyst of coni medullaris and 3 cases of syringomyelus.There were 1 7 cases with fistula in congenital anorectal malformation proved by surgery,including 10 cases of urethral fistula,3 cases of bladder fistula,2 cases of perineal fistula,2 cases of vaginal fistula.9 cases with fistula could be clearly demonstrated on MRI,the others could not be visualized clearly. Conclusion MRI can clearly show the perianal muscles developmental situation and associated malformations in congenital anorectal malformation.MRI has high clinical value in congenital anorectal malformations.