The invention relates to a nervous feedback system based on a real-time functional magnetic resonance signal, comprising a real-time functional magnetic resonance data reading and format transforming module, a real-time functional positioning detection module and a real-time feedback stimulation module, wherein the real-time functional positioning detection module extracts the active mode of the brain of a trainee under a specific task, activates the active state of the brain area through the real-time feedback stimulation module and shows the activated active state to the trainee in a visual way, and the trainee achieves the effect of regulating a specific cognitive function by learning to control the activity level of the activated brain area. The invention detects the activated state of the brain on line through the real-time functional magnetic resonance signal, feeds back to the trainee in real time, enhances or recovers the corresponding cognitive function of the trainee by repeatedly training, regulating and controlling the cognitive activity level of the brain and has important social value on aspects, i.e. brain function mechanism research, brain perceptive and cognitive ability regulation, treatment of diseases related to cognition, and the like.