Trainees need to perform a certain number of endoscopic procedures to achieve competence. Training on simulators is advantageous because it reduces the number of potentially life-threatening critical mistakes. The change in medical practice that limits education time and patient availability, and the increase in medical legal awareness, have contributed to the greater use of simulators in medical training and education. Simulators are of three types: mechanical, animal, and computer based. Progress in computer technology is expected to promote computer-based simulators. At present, the computer-based simulator is helpful in teaching upper and lower gastrointestinal endoscopy, for diagnostic and some therapeutic procedures. It has been used at workshops and live demonstrations performed during endoscopic meetings. It is predicted that with further technological improvement, training on simulators will become obligatory before performing on humans.