CoTras-G is a cognitive training system for a group of people with mild cognitive impairment and normal elderly people at geriatric hospitals, day care centers, rehabilitation centers and elderly centers. It is composed of 145 contents of training that can implement both cognitive assessment and group training simultaneously. Mobile tablets are used in training can perform individual, competitive, cooperation, memory recollection, visual training and evaluation at the same time. Based on the real-time data received through wireless connection, data and comparative analysis will be automatically stored in a tablet PC used by the administrator.