There are some job characteristics of aviation mechanics such as wide skills required for aircraft maintenance, a capacity of handling time for aircraft dispatch, nightshift during poor biorhythm condition, outside work circumstances exposing to snow, rain, heat, cold and so on. Therefore as long as mechanics have the limitations of human performance, human errors during maintenance works can be inevitable. From this point of view, we will study error models and theories and then think about method of preventing and controlling errors occurred during aircraft maintenance.