Reno-colic fistula is a rare entity that to our knowledge has not previously been reported as a complication of penetrating abdominal trauma. We report a case of reno-colic fistula complicating primary repair of a colonic wound from a gunshot to the abdomen. Causes of previously reported reno-colic fistulas include primary renal and colonic pathologic states involving infectious, malignant, or other inflammatory processes. The occurrence of this complication may have been related to the primary repair of the colon. Although recent reports support primary colonic repair, perhaps renal injuries deserve special consideration when patients are evaluated for primary versus staged repair of penetrating injuries.