Inappropriate therapies for hemorrhoids can lead to various complications including anorectal stricture. We report a patient presenting with catastrophic rectal perforation due to severe anal stricture after inappropriate hemorrhoid treatment. A 67-years old man with perianal pain visited the emergency room. The hemorrhoids accompanied by constipation, had tortured him since his youth. Thus he had undergone injection sclerotherapy several times by an unlicensed therapist and hemorrhoidectomy twice at the clinics of private practitioners. His body temperature was as high as 38.5℃. The computed tomographic scan showed a focal perforation of posterior rectal wall. The emergency operation was performed. The fibrotic tissues of the anal canal were excised. And then a sigmoid loop colostomy was constructed. The patient was discharged four days following the operation. This report calls attention to the enormous risk of unlicensed injection sclerotherapy and overzealous hemorrhoidectomy resulting in scarring, progressive stricture, and eventual rectal perforation.