In order to study the cognitive fatigue behavior in false memory, this paper mainly studies related behavior data and brain evoked potential characteristics in cognitive fatigue. Based on the middle school students' fatigue degree in the recognition of false word memory and the characteristics of Brain evoked potential characteristics of recognition judgment, the study uses the research mode of "learning-recognition" to analyze and compare the behavioral features and Brain evoked potential characteristics of different cognitive fatigue in false word memory tasks. The study finds that in the false word memory tasks, the correct rate of correct memory is significantly higher than the correct rate of correct negation, and the P200 amplitude of correct negation is significantly lower than that of missing report while the LPC amplitude induced by the frontal area of the brain in the high cognitive fatigue group is more positive. The latency of N100 and P200 in the high cognitive fatigue group is significantly shorter than that of non-cognitive fatigue and the N100 amplitude in the high cognitive fatigue group is significantly higher than that of the non-cognitive fatigue group in most cases. The experiments show that the use of cognitive fatigue as a measure of individual cognitive ability is very effective. Tian H., Cognitive Fatigue in Memory Task Error of Middle School Students based on Brain Evoked Potential eISSN 1303-5150 www.neuroquantology.com 675 synchronization. International Journal of Psychophysiology 2015; 97(2): 120-30. Sundgren M, Wahlin Å, Maurex L, Brismar T. Event related potential and response time give evidence for a physiological reserve in cognitive functioning in relapsing-remitting multiple sclerosis.