Anal diseases are very common and it is important for a medical practitioner to understand how to deal with these diseases. To establish diagnoses of specific conditions, detailed history taking, inspection, palpation including digital rectal examination, and anoscopic examination are performed. Sigmoidoscopy is also required if upper lesions are suspected. History taking should include information about bleeding, prolapse, swelling, pain, discharge, irritation, bowel habit, continence, abdominal symptoms, weight loss. Sims' position and lithotomy position are commonly used for physical examination of the anal area. In addition to careful inspection and palpation, digital rectal examination should be performed to evaluate the anal canal width and sphincter strength. Above all, digital examination is a very useful and cheap tool to find rectal cancer which commonly occurs after middle-ages. Common anal diseases such as hemorrhoids, anal fissure, perianal abscess and fistula-in-ano, pruritus anai, and rectal prolapse are reviewed.