We present a variation named splenodiaphragmatic or retrosplenic interposition of the colon in three patients aged 6, 70, and 71 years who suffered from different symptoms. The cases were found in 1,000 thoracoabdominal CT scans examined at the radiology clinic between 1999 and 2001. The upper part of descending colon was seen to be between the spleen and the left kidney on abdominal CT scans with contrast enema in the patient aged 71 years. In a 6 year-old child, part of the left colic flexure in the intestinal gas patterns was located between the left kidney and spleen, extending up to the diaphragm in the left hypochondrium on radiological examinations. The left colic flexure and the beginning of the descending colon were imaged on CT behind the spleen at the level of the 11th thoracic vertebra in the third patient aged 70 years. Hepatodiaphragmatic interposition of the colon has been reported previously in many patients; however, no detailed reports are available dealing with the interposition of the descending colon between the diaphragm and spleen. Three cases with retrosplenic colon variation were investigated in detail in the present study. The significance of retrosplenic colon is discussed. It is concluded that the identification of this anatomical variation could avoid unnecessary colon perforation during percutaneous nephrostomy, splenostomy, biopsy, or splenectomy.