Background and aim of work: The colon is the primary target of many functional and pathological disorders, which may have an acute or chronic presentation. This retrospective study was designed to identify the pattern of colorectal diseases in the Egyptian population in colonoscopic examination during the last 3 years. Patients and methods: The files of 1500 patients who presented to Gastrointestinal Endoscopy Unit, Kasr EL-Aini Hospital during the period from 1998-2000, were retrospectively studied, and their findings were plotted in data sheet for further study. Results: Inflammatory and/or ulcerative colonic lesions were found in (25.1%) of cases while (19.7%) of cases showed colonic polyps. Colonic mass was found in (10.2 %) of cases and diverticulosis was detected in (3 %) of cases. Primary piles were found in (17.06%) of cases while normal colonic mucosa was found in (25%) of cases. Other colonic lesions as angiodysplasia, colonic stenotic lesions, anal fissure, rectal varices, fistulae, uretero-colic implantation, and foreign body were found in (3.6%) of cases.Conclusions: Inflammatory and ulcerative colonic lesions are the most common colorectal lesions, followed by colorectal polyps. Colorectal carcinoma is a common malignant neoplasm in Egypt. Colonoscopy is considered a crucial investigating tool in different colorectal diseases as it provides tissue diagnosis by taking a biopsy and allows therapeutic intervention as polypectomy of adenomatous polyps.